watqual2.f

水文模型的原始代码

      subroutine watqual2

!!    ~ ~ ~ PURPOSE ~ ~ ~
!!    this subroutine performs in-stream nutrient transformations and water
!!    quality calculations

!!	adapted by Ann van Griensven, Belgium

!!    ~ ~ ~ INCOMING VARIABLES ~ ~ ~
!!    name         |units         |definition
!!    ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
!!    ai0          |ug chla/mg alg|ratio of chlorophyll-a to algal biomass
!!    ai1          |mg N/mg alg   |fraction of algal biomass that is nitrogen
!!    ai2          |mg P/mg alg   |fraction of algal biomass that is phosphorus
!!    ai3          |mg O2/mg alg  |the rate of oxygen production per unit of
!!                                |algal photosynthesis
!!    ai4          |mg O2/mg alg  |the rate of oxygen uptake per unit of algae
!!                                |respiration
!!    ai5          |mg O2/mg N    |the rate of oxygen uptake per unit of NH3
!!                                |nitrogen oxidation
!!    ai6          |mg O2/mg N    |the rate of oxygen uptake per unit of NO2
!!                                |nitrogen oxidation
!!    algae(:)     |mg alg/L      |algal biomass concentration in reach
!!    ammonian(:)  |mg N/L        |ammonia concentration in reach
!!    bc1(:)       |1/day         |rate constant for biological oxidation of NH3
!!                                |to NO2 in reach at 20 deg C
!!    bc2(:)       |1/day         |rate constant for biological oxidation of NO2
!!                                |to NO3 in reach at 20 deg C
!!    bc3(:)       |1/day         |rate constant for hydrolysis of organic N to
!!                                |ammonia in reach at 20 deg C
!!    bc4(:)       |1/day         |rate constant for the decay of organic P to
!!                                |dissolved P in reach at 20 deg C
!!    chlora(:)    |mg chl-a/L    |chlorophyll-a concentration in reach
!!    dayl(:)      |hours         |day length for current day
!!    disolvp(:)   |mg P/L        |dissolved phosphorus concentration in reach
!!    hru_ra(:)    |MJ/m^2        |solar radiation for the day in HRU
!!    igropt       |none          |Qual2E option for calculating the local
!!                                |specific growth rate of algae
!!                                |1: multiplicative:
!!                                |   u = mumax * fll * fnn * fpp
!!                                |2: limiting nutrient
!!                                |   u = mumax * fll * Min(fnn, fpp)
!!                                |3: harmonic mean
!!                                |   u = mumax * fll * 2. / ((1/fnn)+(1/fpp))
!!    inum1        |none          |reach number
!!    inum2        |none          |inflow hydrograph storage location number
!!    k_l          |MJ/(m2*hr)    |half saturation coefficient for light
!!    k_n          |mg N/L        |michaelis-menton half-saturation constant
!!                                |for nitrogen
!!    k_p          |mg P/L        |michaelis-menton half saturation constant
!!                                |for phosphorus
!!    lambda0      |1/m           |non-algal portion of the light extinction
!!                                |coefficient
!!    lambda1      |1/(m*ug chla/L)|linear algal self-shading coefficient
!!    lambda2      |(1/m)(ug chla/L)**(-2/3)
!!                                |nonlinear algal self-shading coefficient
!!    mumax        |1/day         |maximum specific algal growth rate at 20 deg 
!!                                |C
!!    nitraten(:)  |mg N/L        |nitrate concentration in reach
!!    nitriten(:)  |mg N/L        |nitrite concentration in reach
!!    organicn(:)  |mg N/L        |organic nitrogen concentration in reach
!!    organicp(:)  |mg P/L        |organic phosphorus concentration in reach
!!    p_n          |none          |algal preference factor for ammonia
!!    rch_cbod(:)  |mg O2/L       |carbonaceous biochemical oxygen demand in
!!                                |reach 
!!    rch_dox(:)   |mg O2/L       |dissolved oxygen concentration in reach
!!    rchdep       |m             |depth of flow on day
!!    rchwtr       |m^3 H2O       |water stored in reach at beginning of day
!!    rhoq         |1/day         |algal respiration rate at 20 deg C
!!    rk1(:)       |1/day         |CBOD deoxygenation rate coefficient in reach 
!!                                |at 20 deg C
!!    rk2(:)       |1/day         |reaeration rate in accordance with Fickian
!!                                |diffusion in reach at 20 deg C
!!    rk3(:)       |1/day         |rate of loss of CBOD due to settling in reach
!!                                |at 20 deg C
!!    rk4(:)       |mg O2/        |sediment oxygen demand rate in reach
!!                 |  ((m**2)*day)|at 20 deg C
!!    rnum1        |none          |fraction of overland flow
!!    rs1(:)       |m/day         |local algal settling rate in reach at 20 deg
!!                                |C
!!    rs2(:)       |(mg disP-P)/  |benthos source rate for dissolved phosphorus
!!                 |  ((m**2)*day)|in reach at 20 deg C
!!    rs3(:)       |(mg NH4-N)/   |benthos source rate for ammonia nitrogen in
!!                 |  ((m**2)*day)|reach at 20 deg C
!!    rs4(:)       |1/day         |rate coefficient for organic nitrogen
!!                                |settling in reach at 20 deg C
!!    rs5(:)       |1/day         |organic phosphorus settling rate in reach at
!!                                |20 deg C
!!    rttime       |hr            |reach travel time
!!    rtwtr        |m^3 H2O       |flow out of reach
!!    tfact        |none          |fraction of solar radiation computed in the
!!                                |temperature heat balance that is
!!                                |photosynthetically active
!!    tmpav(:)     |deg C         |average air temperature on current day in HRU
!!    varoute(2,:) |m^3 H2O       |water
!!    varoute(4,:) |kg N          |organic nitrogen
!!    varoute(5,:) |kg P          |organic posphorus
!!    varoute(6,:) |kg N          |nitrate
!!    varoute(7,:) |kg P          |soluble phosphorus
!!    varoute(13,:)|kg            |chlorophyll-a
!!    varoute(14,:)|kg N          |ammonium
!!    varoute(15,:)|kg N          |nitrite
!!    varoute(16,:)|kg            |carbonaceous biological oxygen demand
!!    varoute(17,:)|kg O2         |dissolved oxygen
!!    ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

!!    ~ ~ ~ OUTGOING VARIABLES ~ ~ ~
!!    name        |units         |definition
!!    ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
!!    algae(:)    |mg alg/L      |algal biomass concentration in reach
!!    ammonian(:) |mg N/L        |ammonia concentration in reach
!!    chlora(:)   |mg chl-a/L    |chlorophyll-a concentration in reach
!!    disolvp(:)  |mg P/L        |dissolved phosphorus concentration in reach
!!    nitraten(:) |mg N/L        |nitrate concentration in reach
!!    nitriten(:) |mg N/L        |nitrite concentration in reach
!!    organicn(:) |mg N/L        |organic nitrogen concentration in reach
!!    organicp(:) |mg P/L        |organic phosphorus concentration in reach
!!    rch_cbod(:) |mg O2/L       |carbonaceous biochemical oxygen demand in
!!                               |reach
!!    rch_dox(:)  |mg O2/L       |dissolved oxygen concentration in reach
!!    soxy        |mg O2/L       |saturation concetration of dissolved oxygen
!!    ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

!!    ~ ~ ~ LOCAL DEFINITIONS ~ ~ ~
!!    name        |units         |definition
!!    ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
!!    algcon      |mg alg/L      |initial algal biomass concentration in reach
!!    algi        |MJ/(m2*hr)    |daylight average, photosynthetically active,
!!                               |light intensity
!!    algin       |mg alg/L      |algal biomass concentration in inflow
!!    ammoin      |mg N/L        |ammonium N concentration in inflow
!!    bc1mod      |1/day         |rate constant for biological oxidation of NH3
!!                               |to NO2 modified to reflect impact of low 
!!                               |oxygen concentration
!!    bc2mod      |1/day         |rate constant for biological oxidation of NO2
!!                               |to NO3 modified to reflect impact of low
!!                               |oxygen concentration
!!    cbodcon     |mg/L          |initial carbonaceous biological oxygen demand
!!                               |concentration in reach
!!    cbodin      |mg/L          |carbonaceous biological oxygen demand 
!!                               |concentration in inflow
!!    chlin       |mg chl-a/L    |chlorophyll-a concentration in inflow
!!    cinn        |mg N/L        |effective available nitrogen concentration
!!    cordo       |none          |nitrification rate correction factor
!!    disoxin     |mg O2/L       |dissolved oxygen concentration in inflow
!!    dispin      |mg P/L        |soluble P concentration in inflow
!!    f1          |none          |fraction of algal nitrogen uptake from
!!                               |ammonia pool
!!    fl_1        |none          |growth attenuation factor for light, based on
!!                               |daylight-average light intensity
!!    fll         |none          |growth attenuation factor for light averaged
!!                               |over the diurnal cycle
!!    fnn         |none          |algal growth limitation factor for nitrogen
!!    fpp         |none          |algal growth limitation factor for phosphorus
!!    gra         |1/day         |local algal growth rate at 20 deg C
!!    jrch        |none          |reach number
!!    lambda      |1/m           |light extinction coefficient
!!    nh3con      |mg N/L        |initial ammonia concentration in reach
!!    nitratin    |mg N/L        |nitrate concentration in inflow
!!    nitritin    |mg N/L        |nitrite concentration in inflow
!!    no2con      |mg N/L        |initial nitrite concentration in reach
!!    no3con      |mg N/L        |initial nitrate concentration in reach
!!    o2con       |mg O2/L       |initial dissolved oxygen concentration in 
!!                               |reach
!!    orgncon     |mg N/L        |initial organic N concentration in reach
!!    orgnin      |mg N/L        |organic N concentration in inflow
!!    orgpcon     |mg P/L        |initial organic P concentration in reach
!!    orgpin      |mg P/L        |organic P concentration in inflow
!!    solpcon     |mg P/L        |initial soluble P concentration in reach
!!    tday        |none          |flow duration (fraction of 24 hr)
!!    thbc1       |none          |temperature adjustment factor for local
!!                               |biological oxidation of NH3 to NO2
!!    thbc2       |none          |temperature adjustment factor for local
!!                               |biological oxidation of NO2 to NO3
!!    thbc3       |none          |temperature adjustment factor for local
!!                               |hydrolysis of organic N to ammonia N
!!    thbc4       |none          |temperature adjustment factor for local
!!                               |decay of organic P to dissolved P
!!    thgra       |none          |temperature adjustment factor for local algal
!!                               |growth rate
!!    thrho       |none          |temperature adjustment factor for local algal
!!                               |respiration rate
!!    thrk1       |none          |temperature adjustment factor for local CBOD
!!                               |deoxygenation
!!    thrk2       |none          |temperature adjustment factor for local oxygen
!!                               |reaeration rate
!!    thrk3       |none          |temperature adjustment factor for loss of
!!                               |CBOD due to settling
!!    thrk4       |none          |temperature adjustment factor for local
!!                               |sediment oxygen demand
!!    thrs1       |none          |temperature adjustment factor for local algal
!!                               |settling rate
!!    thrs2       |none          |temperature adjustment factor for local
!!                               |benthos source rate for dissolved phosphorus
!!    thrs3       |none          |temperature adjustment factor for local
!!                               |benthos source rate for ammonia nitrogen
!!    thrs4       |none          |temperature adjustment factor for local
!!                               |organic N settling rate
!!    thrs5       |none          |temperature adjustment factor for local
!!                               |organic P settling rate
!!    wtmp        |deg C         |temperature of water in reach
!!    wtrin       |m^3 H2O       |water flowing into reach on day
!!    uu          |varies        |variable to hold intermediate calculation
!!                               |result
!!    vv          |varies        |variable to hold intermediate calculation
!!                               |result
!!    wtrtot      |m^3 H2O       |inflow + storage water
!!    ww          |varies        |variable to hold intermediate calculation
!!                               |result
!!    xx          |varies        |variable to hold intermediate calculation
!!                               |result
!!    yy          |varies        |variable to hold intermediate calculation
!!                               |result
!!    zz          |varies        |variable to hold intermediate calculation
!!                               |result
!!    ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

!!    ~ ~ ~ SUBROUTINES/FUNCTIONS CALLED ~ ~ ~
!!    Intrinsic: Log, Exp, Min
!!    SWAT: Theta

!!    ~ ~ ~ ~ ~ ~ END SPECIFICATIONS ~ ~ ~ ~ ~ ~

      use parm

      integer :: jrch
      real :: wtrin, chlin, algin, orgnin, ammoin, nitratin, nitritin
      real :: orgpin, dispin, cbodin, disoxin, tday, wtmp, fll, gra
      real :: lambda, fnn, fpp, algi, fl_1, xx, yy, zz, ww, cinn, heatin
      real :: uu, vv, cordo, f1, algcon, orgncon, nh3con, no2con, no3con
      real :: orgpcon, solpcon, cbodcon, o2con, wtrtot, bc1mod, bc2mod
      real :: thgra = 1.047, thrho = 1.047, thrs1 = 1.024
      real :: thrs2 = 1.074, thrs3 = 1.074, thrs4 = 1.024, thrs5 = 1.024
      real :: thbc1 = 1.083, thbc2 = 1.047, thbc3 = 1.047, thbc4 = 1.047
      real :: thrk1 = 1.047, thrk2 = 1.024, thrk3 = 1.024, thrk4 = 1.060
!      real :: thrk5 = 1.047, thrk6 = 1.0, thrs6 = 1.024, thrs7 = 1.0
	real  ::   dalgae, dchla, dorgn, dnh4, dno2, dno3,dorgp,dsolp
      real  ::   dbod, ddisox  

      jrch = 0
      jrch = inum1

       !! initialize water flowing into reach
       wtrin = 0.
       wtrin = varoute(2,inum2) * (1. - rnum1)

       if (rtwtr / 86400.> 0.01.and.wtrin>0.001) then
!! concentrations





         !! initialize concentration of nutrient in reach
         wtrtot = 0.
         algcon = 0.
         orgncon = 0.
         nh3con = 0.
         no2con = 0.
         no3con = 0.
         orgpcon = 0.
         solpcon = 0.
         cbodcon = 0.
         o2con = 0.
         wtrtot = wtrin + rchwtr




         algcon = algae(jrch)
         orgncon = organicn(jrch)
         nh3con = ammonian(jrch)
         no2con = nitriten(jrch)
         no3con = nitraten(jrch)
         orgpcon =  organicp(jrch)
         solpcon = disolvp(jrch)
         cbodcon = rch_cbod(jrch)
         o2con  = rch_dox(jrch)
	   wtmp = wattemp(jrch)

		

c	write(104,*) 't',jrch,disoxin, wtrin, rch_dox(jrch)	
c         o2con = (disoxin * wtrin + rch_dox(jrch) * rchwtr) / wtrtot

         !! calculate temperature in stream
         !! Stefan and Preudhomme. 1993.  Stream temperature estimation 
         !! from air temperature.  Water Res. Bull. p. 27-45
         !! SWAT manual equation 2.3.13

         if (wtmp <= 0.) wtmp = 0.1

         !! calculate effective concentration of available nitrogen
         !! QUAL2E equation III-15
         cinn = nh3con + no3con

         !! calculate saturation concentration for dissolved oxygen
         !! QUAL2E section 3.6.1 equation III-29
         ww = 0.
         xx = 0.
         yy = 0.
         zz = 0.
         ww = -139.34410 + (1.575701e05 / (wtmp + 273.15))
         xx = 6.642308e07 / ((wtmp + 273.15)**2)
         yy = 1.243800e10 / ((wtmp + 273.15)**3)
         zz = 8.621949e11 / ((wtmp + 273.15)**4)
         soxy = Exp(ww - xx + yy - zz)
         if (soxy < 1.e-6) soxy = 0. 
!! end initialize concentrations

!! O2 impact calculations
        !! calculate nitrification rate correction factor for low
        !! oxygen QUAL2E equation III-21
        cordo = 0.
!       write(104, *) o2con, 'o'
	o2con2=o2con
	if (o2con2.le.0.1) o2con2=0.1
	if (o2con2.gt.30.) o2con2=30.
        cordo = 1.0 - Exp(-0.6 * o2con2)