wetlan.f

水文模型的原始代码

      subroutine wetlan
      
!!    ~ ~ ~ PURPOSE ~ ~ ~
!!    this subroutine simulates wetlands     

!!    ~ ~ ~ INCOMING VARIABLES ~ ~ ~
!!    name        |units         |definition
!!    ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
!!    bw1(:)      |none          |1st shape parameter for wetland surface area
!!                               |equation
!!    bw2(:)      |none          |2nd shape parameter for the wetland surface
!!                               |area equation
!!    chlaw(:)    |none          |chlorophyll-a production coefficient for 
!!                               |wetland
!!    hru_dafr(:) |none          |fraction of watershed area in HRU
!!    hru_ha(:)   |ha            |area of HRU in hectares
!!    ihru        |none          |HRU number
!!    ipnd1(:)    |none          |beginning month of 2nd "season" of nutrient
!!                               |settling
!!    ipnd2(:)    |none          |ending month of 2nd "season" of nutrient
!!                               |settling
!!    minpgw(:)   |kg P/ha       |soluble P loading to reach in groundwater
!!    no3gw(:)    |kg N/ha       |nitrate loading to reach in groundwater
!!    nsetlw(1,:) |m/day         |nitrogen settling rate for 1st season
!!    nsetlw(2,:) |m/day         |nitrogen settling rate for 2nd season
!!    pet_day     |mm H2O        |potential evapotranspiration for day in HRU
!!    psetlw(1,:) |m/day         |phosphorus settling rate for 1st season
!!    psetlw(2,:) |m/day         |phosphorus settling rate for 2nd season
!!    qdr(:)      |mm H2O        |net water loading from HRU to main channel
!!    secciw(:)   |none          |water clarity coefficient for wetland
!!    sed_stl(:)  |kg/kg         |fraction of sediment remaining suspended in
!!                               |impoundment after settling for one day
!!    sedminpa(:) |kg P/ha       |amount of active mineral phosphorus sorbed to
!!                               |sediment in surface runoff in HRU for day
!!    sedminps(:) |kg P/ha       |amount of stable mineral phosphorus sorbed to
!!                               |sediment in surface runoff in HRU for day
!!    sedorgn(:)  |kg N/ha       |amount of organic nitrogen in surface runoff
!!                               |in HRU for the day
!!    sedorgp(:)  |kg P/ha       |amount of organic phosphorus in surface runoff
!!                               |in HRU for the day
!!    sedyld(:)   |metric tons   |daily soil loss caused by water erosion in HRU
!!    shallst(:)  |mm H2O        |depth of water in shallow aquifer
!!    subp(:)     |mm H2O        |precipitation for the day in HRU
!!    surqno3(:)  |kg N/ha       |amount of NO3-N in surface runoff in HRU for
!!                               |the day
!!    surqsolp(:) |kg P/ha       |amount of soluble phosphorus in surface runoff
!!                               |in HRU for the day
!!    wet_fr(:)   |none          |fraction of HRU/subbasin area that drains
!!                               |into wetlands
!!    wet_k(:)    |mm/hr         |hydraulic conductivity of bottom of wetlands
!!    wet_mxvol(:)|m^3 H2O       |volume of water required to fill wetlands to
!!                               |maximum water level
!!    wet_no3(:)  |kg N          |amount of nitrate originating from surface
!!                               |runoff in wetland at beginning of day
!!    wet_no3g(:) |kg N          |amount of nitrate originating from
!!                               |groundwater in wetland at beginning of day
!!    wet_no3s(:) |kg N          |amount of nitrate originating from lateral
!!                               |flow in wetland at beginning of day
!!    wet_nsed(:) |kg/L          |normal sediment concentration in wetland water
!!    wet_nvol(:) |m^3 H2O       |volume of water needed to
!!                               |fill wetlands to normal water level
!!    wet_orgn(:) |kg N          |amount of organic N originating from
!!                               |surface runoff in wetland at beginning of day
!!    wet_orgp(:) |kg P          |amount of organic P originating from
!!                               |surface runoff in wetland at beginning of day
!!    wet_psed(:) |kg P          |amount of mineral P attached to sediment
!!                               |originating from surface runoff in wetland at
!!                               |beginning of day
!!    wet_sed(:)  |kg/L          |sediment concentration in wetland water
!!    wet_solp(:) |kg P          |amount of soluble P originating from surface
!!                               |runoff in wetland at beginning of day
!!    wet_solpg(:)|kg P          |amount of soluble P originating from
!!                               |groundwater in wetland at beginning of day
!!    wet_vol(:)  |m^3 H2O       |volume of water in wetlands
!!    ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

!!    ~ ~ ~ OUTGOING VARIABLES ~ ~ ~
!!    name        |units         |definition
!!    ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
!!    qdr(:)      |mm H2O        |net water loading from HRU to main channel
!!    sedyld(:)   |metric tons   |daily soil loss caused by water erosion in HRU
!!    shallst(:)  |mm H2O        |depth of water in shallow aquifer
!!    twlwet      |mm H2O        |water lost through seepage from wetlands on
!!                               |day in HRU
!!    wet_chla(:) |kg chla       |amount of chlorophyll-a in wetland at end
!!                               |of day
!!    wet_no3(:)  |kg N          |amount of nitrate originating from surface
!!                               |runoff in wetland at end of day
!!    wet_no3g(:) |kg N          |amount of nitrate originating from
!!                               |groundwater in wetland at end of day
!!    wet_no3s(:) |kg N          |amount of nitrate originating from lateral
!!                               |flow in wetland at end of day
!!    wet_orgn(:) |kg N          |amount of organic N originating from
!!                               |surface runoff in wetland at end of day
!!    wet_orgp(:) |kg P          |amount of organic P originating from
!!                               |surface runoff in wetland at end of day
!!    wet_psed(:) |kg P          |amount of mineral P attached to sediment
!!                               |originating from surface runoff in wetland at
!!                               |end of day
!!    wet_seci(:) |m             |secchi-disk depth in wetland at end of day
!!    wet_sed(:)  |kg/L          |sediment concentration in wetland water
!!    wet_solp(:) |kg P          |amount of soluble P originating from surface
!!                               |runoff in wetland at end of day
!!    wet_solpg(:)|kg P          |amount of soluble P originating from
!!                               |groundwater in wetland at end of day
!!    wet_vol(:)  |m^3 H2O       |volume of water in wetlands
!!    wetev       |m^3 H2O       |evaporation from wetland for day
!!    wetflwi     |m^3 H2O       |volume of water flowing in wetland on day
!!    wetflwo     |m^3 H2O       |volume of water flowing out wetland on day
!!    wetpcp      |m^3 H2O       |precipitation on wetland for day
!!    wetsedc     |metric tons   |net change in sediment in wetland on day
!!    wetsedi     |metric tons   |sediment loading to wetland for day
!!    wetsedo     |metric tons   |sediment loading from wetland for day
!!    wetsep      |m^3 H2O       |seepage from wetland bottom for day
!!    ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

!!    ~ ~ ~ LOCAL DEFINITIONS ~ ~ ~
!!    name        |units         |definition
!!    ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
!!    cnv         |none          |conversion factor (mm/ha => m^3)
!!    iseas       |none          |nutrient settling rate season
!!    j           |none          |HRU number
!!    nitrok      |none          |fraction of nitrogen in wetland removed by
!!                               |settling
!!    phosk       |none          |fraction of phosphorus in wetland removed by
!!                               |settling
!!    sed         |kg/kg         |sediment concentration in wetland at beginning
!!                               |of day
!!    tpco        |ppb (ug/L)    |concentration of phosphorus in pond water
!!                               |on day
!!    vol         |m^3 H2O       |volume of wetland at beginning of day
!!    wetsa       |ha            |surface area of wetland on current day
!!    xx          |none          |variable to hold intermediate calculation
!!    ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

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

      use parm

      integer :: j, iseas
      real :: vol, cnv, sed, wetsa, xx, phosk, nitrok, tpco

      j = 0
      j = ihru

      if (wet_fr(j) > 0.) then
        cnv = 0.
        cnv = hru_ha(j) * 10.               !conversion factor
        
        !! store initial values
        vol = 0.
        sed = 0.
        vol = wet_vol(j)
        sed = wet_sed(j)

        !! calculate water balance for day
        wetsa = 0.
        wetsa = bw1(j) * wet_vol(j) ** bw2(j)

        wetev = 10. * evwet(j) * pet_day * wetsa
        wetsep = wet_k(j) * wetsa * 240.
        wetpcp = subp(j) * wetsa * 10.

        !! calculate water flowing into wetland from HRU
        wetflwi = qdr(j) * 10. * (hru_ha(j) * wet_fr(j) - wetsa)
        qdr(j) = qdr(j) - qdr(j) * wet_fr(j)
       
        !! sediment loading to wetland from HRU
        wetsedi = sedyld(j) * (wet_fr(j) - (wetsa / hru_ha(j)))
        sedyld(j) = sedyld(j) - sedyld(j) * wet_fr(j)

        !! compute nitrogen and phosphorus levels in wetland at beginning
        !! of day
        !! equation 29.1.1 in SWAT manual
        xx = 0.