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lpmorenoc / dssat-csm-os

DSSAT Cropping System Model
BSD 3-Clause "New" or "Revised" License
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Modify leaf appearance curve #35

Closed lpmorenoc closed 3 years ago

lpmorenoc commented 3 years ago

Currently the leaf appearance curve works ok with branching varieties but it underestimates the number of leaves for the non-branching varieties (see example below for TME 419). image

James suggested to use a linear curve and reduce the leaf appearance rate when the assimilates, water or nitrogen are not enough to supply the demand. Currently we are reducing the leaf appearance when there is water stress and nitrogen stress. These are some testing for non-branching varieties using linear regression (in Excel): image And the model Wang-Engel: image

lpmorenoc commented 3 years ago

Now we have two independent curves for branching vs. non-branching or late branching varieties (thermal time for first branching >1200):

IF (PDL(1) < 1200.) THEN
                IF (DAE > 0) THEN
                    IF (ISWWAT == 'Y') THEN
                        IF (ISWNIT /= 'N') THEN
                            LNUMG = ((1.048488E6*LNSLP)/((((3.5986E3))+DAWWP)**2))*TT* (AMIN1(WFG,NFG)) * WFGREA  
                        ELSE
                            LNUMG = ((1.048488E6*LNSLP)/((((3.5986E3))+DAWWP)**2))*TT* WFG  * WFGREA                                      !LPM 31JUL2015 to consider water stress
                        ENDIF
                    ELSE
                        LNUMG = ((1.048488E6*LNSLP)/((((3.5986E3))+DAWWP)**2))*TT                                              !LPM 21/02/2015 leaf number curve
                    ENDIF
                ELSEIF (DAG > 0) THEN
                    IF (ISWWAT == 'Y') THEN
                        IF (ISWNIT /= 'N') THEN
                            LNUMG = ((1.048488E6*LNSLP)/((((3.5986E3))+DAWWP)**2))*TTGEM*(AMIN1(WFG,NFG)) * WFGREA                               !LPM 31JUL2015 to consider water stress
                        ELSE
                            LNUMG = ((1.048488E6*LNSLP)/((((3.5986E3))+DAWWP)**2))*TTGEM * WFG * WFGREA 
                        ENDIF

                    ELSE
                        LNUMG = ((1.048488E6*LNSLP)/((((3.5986E3))+DAWWP)**2)) * Tfgem                                              !LPM 21/02/2015 leaf number curve
                    ENDIF
                ENDIF
            ELSE
                IF (DAE > 0) THEN
                        IF (ISWWAT == 'Y') THEN
                            IF (ISWNIT /= 'N') THEN
                                LNUMG = LNSLP * tfd * (AMIN1(WFG,NFG)) * WFGREA   
                            ELSE
                                LNUMG = LNSLP *tfd * WFG * WFGREA                                       !LPM 31JUL2015 to consider water stress
                            ENDIF
                        ELSE
                            LNUMG = LNSLP * tfd                                              !LPM 21/02/2015 leaf number curve
                        ENDIF
                    ELSEIF (DAG > 0) THEN
                        IF (ISWWAT == 'Y') THEN
                            IF (ISWNIT /= 'N') THEN
                                LNUMG = LNSLP * Tfgem * AMIN1(WFG,NFG) * WFGREA                             !LPM 31JUL2015 to consider water stress
                            ELSE
                                LNUMG = LNSLP * Tfgem * WFG * WFGREA  
                            ENDIF
                        ELSE
                            LNUMG = LNSLP * Tfgem                                              !LPM 21/02/2015 leaf number curve
                        ENDIF
                    ENDIF
            ENDIF