Insect Dynamics - Dynamic Modeling of Diseases and Pests - page 50

TWO STAGE INSECT POPULATION MODEL

ADULTS(t) = ADULTS(t − dt) + (HATCHING − ADULTS DYING) * dt

INIT ADULTS = 0

INFLOWS:
HATCHING = EGGS/T*MSF

OUTFLOWS:
ADULTS DYING = ADULTS*(1 − MASF)/DT

EGGS(t) = EGGS(t − dt) + (BIRTHING − EGGS DYING − HATCHING) * dt

INIT EGGS = 50

INFLOWS:
BIRTHING

= EGG LAY RATE*ADULTS

OUTFLOWS:
EGGS DYING = EGGS*(1 − MSF)/DT

HATCHING = EGGS/T * MSF

EASF = .8* EGG LAY RATE = .5

ESF = .7

MASF = EXP(LOGN(EASF) * DT/TA)

MSF = EXP(LOGN(ESF)/T * DT)

T = 5

TA = 1

MSF

EGGS DYING

BIRTHING

ESF

HATCHING

T

EGGS

ADULTS DYING

EGG LAY RATE

ADULTS

TA

EASF

MASF

Fig. 3.1