INFLOWS:
BIRTHING_H1 ¼ IF (K1 À ALL_ADULTS_1) > 0 THEN BR_H * ADULTS_H1
ELSE 0 {Individuals per Time Period}
OUTFLOWS:
DYING_HN1 ¼ (1 À MNSF_H) * NYMPHS_H1/DT
MATURE_H1 ¼ MNSF_H * NYMPHS_H1/TN1_H * (1ÀINFECTION_COEF1)
INFECTION_1 ¼ INFECTION_COEF1 * MATURE_H1 {Individuals per Time
Period}
NYMPHS_H2(t) ¼ NYMPHS_H2(t À dt) + (BIRTHS_H2 À DYING_HN2 À
MATURE_H2 À INFECTION_2) * dt
INIT NYMPHS_H2 ¼ 0 {Initial Healthy eggs}
INFLOWS:
BIRTHS_H2 ¼ IF (K2-ALL_ADULTS_2) > 0 THEN BR_H * ADULTS_H2
ELSE 0 {Individuals per Time Period}
OUTFLOWS:
DYING_HN2 ¼ (1 À MNSF_H) * NYMPHS_H2/DT {Individuals per Time Period}
MATURE_H2 ¼ MNSF_H * NYMPHS_H2 * (1-INFECTION_COEF2)/TN1_H
{Individuals per Time Period}
INFECTION_2 ¼ INFECTION_COEF2 * MATURE_H2 {Individuals per Time Period}
ALL_ADULTS_1 ¼ ADULTS_H1+ADULTS_D1
ALL_ADULTS_2 ¼ ADULTS_H2+ADULTS_D2
BR_D ¼ .35 {Experimental laying rate. DISEASED EGGS PER ADULT PER
DAY.}
BR_H ¼ 0.75
DOCUMENT: NYMPH BIRTH RATE, NYMPHS PER DAY PER ADULT
EASF1_D ¼ .65 {Experimental daily diseased adult survival fraction per stage,
dimensionless.}
EASF1_H ¼ 0.8
FRXNL_CAP1 ¼ ALL_ADULTS_1/K1
DOCUMENT: This fraction is the degree to which both healthy and diseased adults
have reached their carrying capacity.
FRXNL_CAP2 ¼ ALL_ADULTS_2/K2
INFECTION_COEF1 ¼ 1 À EXP(À.3 * NYMPHS_H1 * NYMPHS_D1) {Constructed
function giving the desired 0 to 1 probability.}
INFECTION_COEF2 ¼ 1 À EXP(À.3 * NYMPHS_H2 * NYMPHS_D2) {Constructed
function giving the desired 0 to 1 probability.}
K1 ¼ IF CARRY_R1 > .666 THEN 2 ELSE IF CARRY_R1 < .333 THEN .5
ELSE 1 {This is the carrying capacity of the area the insects area}
K2 ¼ IF CARRY_R2 > .666 THEN 4 ELSE IF CARRY_R2 < .333 THEN 1
ELSE 2 {This is the carrying capacity of the area the insects area}
MASF_D ¼ EXP(LN(EASF1_D)/TA1_D * DT)
MASF_H ¼ EXP(LN(EASF1_H)/TA1_H * DT)
MNSF_D ¼ EXP(LN(S1_D)/TN1_D * DT)
MNSF_H ¼ EXP(LN(S1_H)/TN1_H * DT)
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33 Diseased and Healthy Immigrating Insects