13.5. Questions and Tasks
311
O)+(IF(( .3*Fishwt[15))>Fishwt[18)) THEN (NP_mass[18))
ELSE O)+(IF((.3*Fishwt(15)) >Fishwt[19)) THEN
(NP_mass[19)) ELSE 0)+(IF((.3*Fishwt[15))>Fishwt[20))
THEN (NP_mass(20)) ELSE 0) {quantity of biomass which is
susceptible to cannibalism}
sus_mass [16) = (IF(( .3*Fishwt[16))>Fishwt[17)) THEN
(NP_mass[17)) ELSE O)+(IF((.3*Fishwt(16))>Fishwt[18))
THEN (NP_mass[18)) ELSE
O)+(IF((.3*Fishwt[16))>Fishwt[19)) THEN (NP_mass[19))
ELSE O)+(IF(( .3*Fishwt[16))>Fishwt[20)) THEN
(NP_mass[ 20)) ELSE 0) {quantity of biomass which is
susceptible to cannibalism}
sus_mass [17) = (IF((.3*Fishwt[17))>Fishwt[18)) THEN
(NP_mass[18)) ELSE O)+(IF(( .3*Fishwt[17))>Fishwt[19))
THEN (NP_mass[19)) ELSE
O)+(IF((.3*Fishwt[17))>Fishwt[20)) THEN (NP_mass[20))
ELSE 0) {quantity of biomass which is susceptible to
cannibalism}
sus_mass [18) = (IF(( .3*Fishwt[18))>Fishwt[19)) THEN
(NP_mass[19)) ELSE O)+(IF(( .3*Fishwt[18))>Fishwt[20))
THEN (NP_mass[20)) ELSE 0) {quantity of biomass which is
susceptible to cannibalism}
sus_mass (19) = (IF((.3*Fishwt[19))>Fishwt[20)) THEN
(NP_mass[20)) ELSE 0) {quantity of biomass which is
susceptible to cannibalism}
sus_mass (20) =
(NP_mass [l)+NP_mass (2)+NP_mass (3)+NP_mass (4)+NP_mass[5 )
+NP_mass(6)+NP_mass(7]+NP_mass(8)+NP_mass(9]+NP_mass(l0
)+NP_mass[ll)+NP_mass(12)+NP_mass[13)+NP_mass[14)+NP_ma
ss(15)+NP_mass[16)+NP_mass[17)+NP_mass(18)+NP_mass(19)+
Fishwt (l)+Fishwt (2)+Fishwt (3)+Fishwt(4)+Fishwt (5)+Fishw
t(6)+Fishwt(7)+Fishwt(8)+Fishwt(9)+Fishwt(lO)+Fishwt(l1
)+Fishwt(12)+Fishwt(13)+Fishwt(14)+Fishwt(15)+Fishwt(l6
)+Fishwt(17)+Fishwt(18)+Fishwt(19))*O
Nile Perch Biomass
Total_fished_number(t)
(tot_fished_num) * dt
Total_fished_number(t-dt) +
INIT Total fished_number = 0 {number of fish caught by
fishery}
INFLOWS :
tot_fished_num = ARRAYSUM(fished_mortality(*))