Pesticide is removed from the water body in outflow. The amount of dissolved and particulate pesticide removed from the water body in outflow is:
pstsol,oβ=QβVFdββpstlkwtrββ 8:4.1.14
pstsorb,oβ=QβVFpββpstlkwtrββ 8:4.1.15
where pstsol,oβ is the amount of dissolved pesticide removed via outflow (mg pst), pstsorb,oβ is the amount of particulate pesticide removed via outflow (mg pst), Q is the rate of outflow from the water body (m3 H2βO/day), Fdβ is the fraction of total pesticide in the dissolved phase, Fpβ is the fraction of total pesticide in the particulate phase, pstlkwtrβ is the amount of pesticide in the water (mg pst), and V is the volume of water in the water body (m3 H2βO).
Table 8:4-1: SWAT+ input variables that pesticide partitioning.
: Pesticide settling velocity (m/day)
.lwq
LKPST_KOC
Kdβ: Pesticide partition coefficient (m3/g)
.lwq
LKPST_REA
kp,aqβ: Rate constant for degradation or removal of pesticide in the water (1/day)
.lwq
LKPST_VOL
vvβ: Volatilization mass-transfer coefficient (m/day)
.lwq
LKPST_STL