subroutine pl_leaf_senes use plant_data_module use basin_module use hru_module, only : hru, ihru, ipl use plant_module use plant_data_module use carbon_module use organic_mineral_mass_module use climate_module use hydrograph_module implicit none integer :: j = 0 !none |HRU number integer :: idp = 0 ! | integer :: iob = 0 ! | integer :: iwgn = 0 ! | real :: rto = 0. !none |ratio of current years of growth:years to maturity of perennial real :: ppet = 0. !mm/mm |running average of precip over pet real :: leaf_tov_mon = 0. !months |leaf turnover rate months real :: coef = 0. ! |coefficient for ppet - leaf turnover equation real :: exp_co = 0. ! |exponent for ppet - leaf turnover equation real :: lai_init = 0. ! |lai before senescence real :: lai_drop = 0. ! |lai decline due to senescence j = ihru idp = pcom(j)%plcur(ipl)%idplt leaf_drop%m = 0. !! lai decline for annuals - if dlai < phuacc < 1 if (pldb(idp)%typ == "warm_annual" .or. pldb(idp)%typ == "cold_annual" .or. & pldb(idp)%typ == "warm_annual_tuber" .or. pldb(idp)%typ == "cold_annual_tuber") then if (pcom(j)%plcur(ipl)%phuacc > pldb(idp)%dlai .and. pcom(j)%plcur(ipl)%phuacc < 1.) then lai_init = pcom(j)%plg(ipl)%lai rto = (1. - pcom(j)%plcur(ipl)%phuacc) / (1. - pcom(j)%plg(ipl)%dphu) pcom(j)%plg(ipl)%lai = pcom(j)%plg(ipl)%olai * rto ** pldb(idp)%dlai_rate !! compute leaf biomass drop !if (lai_init > 1.e-6) then ! lai_drop = (lai_init - pcom(j)%plg(ipl)%lai) / lai_init ! lai_drop = max (0., lai_drop) ! lai_drop = amin1 (1., lai_drop) ! leaf_drop%m = lai_drop * pl_mass(j)%leaf(ipl)%m ! leaf_drop%n = leaf_drop%m * pcom(j)%plm(ipl)%n_fr ! leaf_drop%n = max (0., leaf_drop%n) ! leaf_drop%p = leaf_drop%m * pcom(j)%plm(ipl)%p_fr ! leaf_drop%p = max (0., leaf_drop%p) !end if end if end if !! lai decline for temperature based perennials if (pldb(idp)%typ == "perennial" .and. pldb(idp)%trig == "temp_gro") then if (pcom(j)%plcur(ipl)%phuacc > pldb(idp)%dlai .and. pcom(j)%plg(ipl)%d_senes < 15.) then iob = hru(j)%obj_no iwst = ob(iob)%wst lai_init = pcom(j)%plg(ipl)%lai !! use 15 day senescence period pcom(j)%plg(ipl)%d_senes = pcom(j)%plg(ipl)%d_senes + 1. rto = 1. - (pcom(j)%plg(ipl)%d_senes / 15.) !! assume 15 day senescence and leaf drop pcom(j)%plg(ipl)%lai = (pcom(j)%plg(ipl)%olai - pldb(idp)%alai_min) * rto + pldb(idp)%alai_min pcom(j)%plg(ipl)%lai = max (pcom(j)%plg(ipl)%lai, pldb(idp)%alai_min) !! logistic decline rate - Strauch and Volk !pcom(j)%plg(ipl)%lai = (pcom(j)%plg(ipl)%olai - pldb(idp)%alai_min) / & ! (1. + Exp((rto - .5) * (-12))) + pldb(idp)%alai_min !if (j==1866) then !write (2222, *) time%day, time%mo, time%yrc, j, pcom(j)%plg(ipl)%lai, pl_mass(j)%leaf(ipl)%m !end if !! compute leaf biomass drop if (lai_init > 0.05) then lai_drop = (lai_init - pcom(j)%plg(ipl)%lai) / lai_init else lai_drop = 0. end if lai_drop = max (0., lai_drop) lai_drop = amin1 (1., lai_drop) leaf_drop%m = lai_drop * pl_mass(j)%leaf(ipl)%m leaf_drop%n = leaf_drop%m * pcom(j)%plm(ipl)%n_fr leaf_drop%n = max (0., leaf_drop%n) leaf_drop%p = leaf_drop%m * pcom(j)%plm(ipl)%p_fr leaf_drop%p = max (0., leaf_drop%p) end if end if !! lai decline for moisture based perennials - use f(P/PET) to estimate drought stress if (pldb(idp)%typ == "perennial" .and. pldb(idp)%trig == "moisture_gro") then iob = hru(j)%obj_no iwst = ob(iob)%wst iwgn = wst(iwst)%wco%wgn !! linear lai decline based on soil moisture (max loss at p/pet=0.1, min loss at p/pet=0.5) ppet = wgn_pms(iwgn)%precip_sum / wgn_pms(iwgn)%pet_sum if (ppet < 0.5) then coef = 1. ! / .36 exp_co = -10. * ppet + 6. leaf_tov_mon = coef * exp (-exp_co) * (pldb(idp)%leaf_tov_min - pldb(idp)%leaf_tov_max) + pldb(idp)%leaf_tov_max !leaf_tov_mon = pldb(idp)%leaf_tov_min - (0.5 - ppet) * (pldb(idp)%leaf_tov_min - pldb(idp)%leaf_tov_max) / 0.4 else leaf_tov_mon = pldb(idp)%leaf_tov_min end if leaf_tov_mon = amin1 (leaf_tov_mon, pldb(idp)%leaf_tov_min) leaf_tov_mon = max (leaf_tov_mon, pldb(idp)%leaf_tov_max) !! daily turnover - from monthly turnover rate pcom(j)%plcur(ipl)%leaf_tov = (1. / (30. * leaf_tov_mon)) !! assume an lai-biomass relationship - linear with slope = 0.0002 LAI/leaf biomass(kg/ha) ***should be plant parm in plants.plt pcom(j)%plg(ipl)%lai = pcom(j)%plg(ipl)%lai - pcom(j)%plcur(ipl)%leaf_tov !pcom(j)%plg(ipl)%lai = max (pcom(j)%plg(ipl)%lai, pldb(idp)%alai_min) !! compute leaf biomass drop leaf_drop%m = pcom(j)%plcur(ipl)%leaf_tov * pl_mass(j)%leaf(ipl)%m leaf_drop%n = leaf_drop%m * pcom(j)%plm(ipl)%n_fr leaf_drop%n = max (0., leaf_drop%n) leaf_drop%p = leaf_drop%m * pcom(j)%plm(ipl)%p_fr leaf_drop%p = max (0., leaf_drop%p) end if if (leaf_drop%m > 0.) then rsd1(j)%tot(ipl) = rsd1(j)%tot(ipl) + leaf_drop rsd1(j)%tot(ipl)%m = Max(rsd1(j)%tot(ipl)%m, 0.) pl_mass(j)%leaf(ipl) = pl_mass(j)%leaf(ipl) - leaf_drop pl_mass(j)%tot(ipl) = pl_mass(j)%tot(ipl) - leaf_drop pl_mass(j)%ab_gr(ipl) = pl_mass(j)%ab_gr(ipl) - leaf_drop hrc_d(j)%plant_c = hrc_d(j)%plant_c + pl_mass(j)%ab_gr(ipl)%c hpc_d(j)%drop_c = hpc_d(j)%drop_c + pl_mass(j)%ab_gr(ipl)%c end if return end subroutine pl_leaf_senes