Changes between Version 130 and Version 131 of DevelopmentActivities/ORCHIDEE-CNP
- Timestamp:
- 2017-07-20T16:13:48+02:00 (7 years ago)
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DevelopmentActivities/ORCHIDEE-CNP
v130 v131 6 6 The phosphorus cycle and the model evaluation at two sites along a soil formation chronosequence is published at GMD [https://www.geosci-model-dev-discuss.net/gmd-2017-62/]. 7 7 8 == 3. Conceptual modifications to the nitrogen cycle ==8 == 1. Conceptual modifications to the nitrogen cycle == 9 9 10 === 3.1 soil mineral N concentration in soil solution ===10 === 1.1 soil mineral N concentration in soil solution === 11 11 Following Smith et al (2014), I introduced the use of the maximum water holding capacity of soils (max_var_eau) to approximate pore space which to derive the average soil mineral N concentration in solution. The use of the actual water volume can not be recommended as we this would lead to high N concentration in soil water when soil water is very low. As we do not account for the inhibition of replenishment of mineral N in the soil solution around roots when soil water is scarce. 12 12 13 === 3.2 soil mineral N dynamics ===13 === 1.2 soil mineral N dynamics === 14 14 15 15 ORCHIDEE-CN performs poorly in respect to soil mineral N dynamics. This is due to two reason. First, ORCHIDEE-CN is based on Zaehle & Friend (2010) and does not incorporate the modification to the DNDC formulations which avoid instabilities when run on global scale (Zaehle et al., 2011). Second, most of the modifications in ORCHIDEE-CN I assume are not tested, as most of the environmental scaling function "explode" with the parameter set used, or are not sound imo. … … 23 23 This needs to be corrected in the near future. 24 24 25 == 4. Re-calibration of the carbon cycle ==25 == 2. Re-calibration of the carbon cycle == 26 26 The calibration of ORCHIDEE-CAN of the carbon cycle in combination with the Vcmax being derived from leaf nitrogen content, leads to unrealistic C cycle (CUE, biomass stocks, biomass turnover, etc.). 27 27 Using as a guide rough ranges of observation-based estimates of aboveground biomass, LAI, CUE, and biomass turnover, we manipulated parameters of the pipe model (TAU_SAP, KLATOSA_MIN, K_LATOSA_MAX) as well as the inversion of the rate constant for tree turnover RESIDENCE_TIME and the factor relating maintenance respiration to tissue N, COEFF_MAINT. … … 37 37 It would be better to have it coupled as this adds a constraint to K_LATOSA. Best would be to include even more constraints on K_LATOSA for example hydrological constraints (like the stuff Emilie develops). 38 38 39 == 5. New input files ==39 == 3. New input files == 40 40 You can find information on the new input files needed for the P cycle here: [https://forge.ipsl.jussieu.fr/orchidee/wiki/DevelopmentActivities/ORCHIDEE-CNP/newInput] 41 41 42 == 6. Notes regarding Vcmax and leaf nutrients == 43 [https://forge.ipsl.jussieu.fr/orchidee/wiki/DevelopmentActivities/ORCHIDEE-CNP/Vcmax] 44 45 == 7. unresolved issues (ideas for future developments) == 42 == 4. unresolved issues (ideas for future developments) == 46 43 47 44 There are still yet unresolved issue with the model. They are listed here: [https://forge.ipsl.jussieu.fr/orchidee/wiki/DevelopmentActivities/ORCHIDEE-CNP/issues] 48 45 49 == 8. Howto install, compile & run the model ==46 == 5. Howto install, compile & run the model == 50 47 You can find information on how to setup the simulations here: [https://forge.ipsl.jussieu.fr/orchidee/wiki/DevelopmentActivities/ORCHIDEE-CNP/howtoUse] 51 48 52 == 9. Prescribing tissue stoichiometry: WARNING ==49 == 6. Prescribing tissue stoichiometry: WARNING == 53 50 At the moment prescribing tissue CN and NP ratio have only a purpose when spinning up the model, but cannot be used for the analysis of nutrient limitation. 54 51 The effect of nutrient limitation on growth is not handled consistently when prescribing leaf CN ratios which are not optimal ratios (CNmin and NPmin).
