module pest_tempdecay_module implicit none contains real function decay_temp_adjust(hl_25, temp, q10) !! Calculates temperature-adjusted decay based on Q10 model !! Need to calculate the temperature-adjusted half-life first !! then re-calculate the decay-rate !! hl_25: pesticide specific half life (soil, foliar or aquatic) at 25 degC !! q10 FOCUS default: 2.2 !! q10 EFSA update 2007: 2.58 !! q10 for plants: 1.22 !! https://efsa.onlinelibrary.wiley.com/doi/epdf/10.2903/j.efsa.2008.622 !! https://archive.epa.gov/epa/sites/production/files/2015-11/documents/attachment_3_-_przm-gw_input_parameter_guidance.pdf real, intent(in) :: hl_25 real, intent(in) :: temp real, optional, intent(in) :: q10 real :: q10_local real :: hl_t q10_local = 2.58 if (present(q10)) q10_local = q10 if (hl_25 <= 0.) then decay_temp_adjust = 0. return end if hl_t = hl_25 * q10_local ** ((25.0 - temp) / 10.0) if (hl_t <= 0.) then decay_temp_adjust = 0. else decay_temp_adjust = exp(-0.693 / hl_t) end if end function decay_temp_adjust end module pest_tempdecay_module