source: branches/publications/ORCHIDEE-MICT-teb/src_sticslai/F_humirac.f90

! *----------------------------------------------------------------* c
! *   introduction d'une fonction continue entre pf4.2 et CC pour  * c
! *   contraindre la germination et la levée                       * c
! *----------------------------------------------------------------* c
!> Introduction of a continuous function between pf4.2 and CC to Constrain germination and emergence
!> calculate the effects of soil moisture in the seedbed on germination and this effect can be estimated by using the parameter of F_humirac as shown below--Xiuchen Wu

module Divers_water

  USE Stics

  IMPLICIT NONE
  PRIVATE
  PUBLIC F_humirac
 
  contains
 
  real function F_humirac(h)
  
    IMPLICIT NONE
  
    real, intent(IN) :: h  
    !real, intent(IN) :: hmin  
    !real, intent(IN) :: hmax      !> // OUTPUT // Maximum height of water table between drains // cm
    !real, intent(IN) :: P_sensrsec  !> // PARAMETER // root sensitivity to drought (1=insensitive) // SD // PARPLT // 1 
    
    !real :: x  
  
        
        if (h > 0) then
           F_humirac = P_sensrsec + (1. - P_sensrsec) * h
        else
           F_humirac = 0
        endif
  
  
  
        if (F_humirac > 1.)  F_humirac = 1.
        if (F_humirac < 0.)  F_humirac = 0.
  
       ! if (hmax /= hmin) then  
       !   !: 10/06/03 - modif de fonction humirac avant pfp pour 
       !   !-            aboutir à une absorption nulle pour h = 0
       !   if (h > hmin) then
       !     x = (h - hmin) / (hmax - hmin)
       !     F_humirac = P_sensrsec + (1. - P_sensrsec) * x
       !   else
       !     F_humirac = P_sensrsec / hmin * h
       !   endif
       ! else
       !   !: NB - 10/06/03
       !   ! --if (h < hmin) humirac = P_sensrsec
       !   if (h >= hmin) then
       !     F_humirac = 1.0
       !   else
       !     F_humirac = P_sensrsec / hmin * h
       !   endif
       ! endif
  
       ! if (F_humirac > 1.)  F_humirac = 1.
       ! if (F_humirac < 0.)  F_humirac = 0.
  
  return
  end function F_humirac
end module Divers_water