*IF DEF,A03_7A MICROB7A.2
C *****************************COPYRIGHT****************************** MICROB7A.3
C (c) CROWN COPYRIGHT 1997, METEOROLOGICAL OFFICE, All Rights Reserved. MICROB7A.4
C MICROB7A.5
C Use, duplication or disclosure of this code is subject to the MICROB7A.6
C restrictions as set forth in the contract. MICROB7A.7
C MICROB7A.8
C Meteorological Office MICROB7A.9
C London Road MICROB7A.10
C BRACKNELL MICROB7A.11
C Berkshire UK MICROB7A.12
C RG12 2SZ MICROB7A.13
C MICROB7A.14
C If no contract has been raised with this copy of the code, the use, MICROB7A.15
C duplication or disclosure of it is strictly prohibited. Permission MICROB7A.16
C to do so must first be obtained in writing from the Head of Numerical MICROB7A.17
C Modelling at the above address. MICROB7A.18
C ******************************COPYRIGHT****************************** MICROB7A.19
!*********************************************************************** MICROB7A.20
! Calculates the soil respiration based on a simplified version of the MICROB7A.21
! model of Raich et al. (1991). MICROB7A.22
!*********************************************************************** MICROB7A.23
SUBROUTINE MICROBE (LAND_FIELD,LAND_PTS,LAND1 1MICROB7A.24
&, CS,STH_SOIL,V_SAT,V_WILT,TSOIL,RESP_S) MICROB7A.25
MICROB7A.26
IMPLICIT NONE MICROB7A.27
MICROB7A.28
INTEGER MICROB7A.29
& LAND_FIELD ! IN Total number of land points. MICROB7A.30
&,LAND_PTS ! IN Number of land points to be MICROB7A.31
! ! processed. MICROB7A.32
&,LAND1 ! IN First land point to be MICROB7A.33
! ! processed. MICROB7A.34
MICROB7A.35
REAL MICROB7A.36
& CS(LAND_FIELD) ! IN Soil carbon (kg C/m2). MICROB7A.37
&,STH_SOIL(LAND_FIELD) ! IN Top layer soil moisture as a MICROB7A.38
! ! fraction of saturation (m3/m3). MICROB7A.39
&,V_SAT(LAND_FIELD) ! IN Volumetric soil moisture MICROB7A.40
! ! concentration at saturation MICROB7A.41
! ! (m3 H2O/m3 soil). MICROB7A.42
&,V_WILT(LAND_FIELD) ! IN Volumetric soil moisture MICROB7A.43
! ! concentration below which MICROB7A.44
! ! stomata close (m3 H2O/m3 soil). MICROB7A.45
! as a fraction of saturation. MICROB7A.46
&,TSOIL(LAND_FIELD) ! IN Soil temperature (K). MICROB7A.47
&,RESP_S(LAND_FIELD) ! OUT Soil respiration (kg C/m2/s). MICROB7A.48
&,FSTH,FTEMP ! WORK Factors describing the MICROB7A.49
! ! influence of soil moisture and MICROB7A.50
! ! soil temperature respectively MICROB7A.51
! ! on the soil respiration. MICROB7A.52
&,STH_OPT ! WORK Fractional soil moisture at MICROB7A.53
! ! which respiration is maximum. MICROB7A.54
&,STH_WILT ! WORK Wilting soil moisture as a MICROB7A.55
! ! fraction of saturation. MICROB7A.56
INTEGER MICROB7A.57
& L ! Loop counter MICROB7A.58
MICROB7A.59
!----------------------------------------------------------------------- MICROB7A.60
! Local parameters MICROB7A.61
!----------------------------------------------------------------------- MICROB7A.62
REAL MICROB7A.63
& KAPS ! Specific soil respiration rate MICROB7A.64
! ! at 25 deg ! and optimum soil MICROB7A.65
! ! moisture (/s). MICROB7A.66
&,Q10 ! Q10 factor for soil respiration. MICROB7A.67
PARAMETER (KAPS = 0.5E-8, Q10 = 2.0) MICROB7A.68
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MICROB7A.70
DO L=LAND1,LAND1+LAND_PTS-1 MICROB7A.71
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IF (V_SAT(L) .GT. 0.0) THEN MICROB7A.73
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STH_WILT = V_WILT(L) / V_SAT(L) MICROB7A.75
STH_OPT = 0.5 * (1 + STH_WILT) MICROB7A.76
MICROB7A.77
IF (STH_SOIL(L) .LE. STH_WILT) THEN MICROB7A.78
FSTH = 0.2 MICROB7A.79
ELSEIF (STH_SOIL(L) .GT. STH_WILT .AND. MICROB7A.80
& STH_SOIL(L) .LE. STH_OPT) THEN MICROB7A.81
FSTH = 0.2 + 0.8 * ((STH_SOIL(L) - STH_WILT) MICROB7A.82
& / (STH_OPT - STH_WILT)) MICROB7A.83
ELSEIF (STH_SOIL(L) .GT. STH_OPT) THEN MICROB7A.84
FSTH = 1 - 0.8 * (STH_SOIL(L) - STH_OPT) MICROB7A.85
ENDIF MICROB7A.86
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FTEMP = Q10 ** (0.1 * (TSOIL(L) - 298.15)) MICROB7A.88
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RESP_S(L) = KAPS * CS(L) * FSTH * FTEMP MICROB7A.90
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ELSE MICROB7A.92
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RESP_S(L) = 0.0 MICROB7A.94
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ENDIF MICROB7A.96
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ENDDO MICROB7A.98
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RETURN MICROB7A.100
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END MICROB7A.102
*ENDIF MICROB7A.103