18.6. Questions and Tasks
409
normal_ext'l_investment = 0
percent_of_land_into_reserve
.01
regulation_of_coastlands = 0
Replanting_switch = 1
stock_loss_fraction =
1 /40*effect_of_coastal_eff_on_aqua
stock-per_hectare = 220
time_to_develop-ponds = 6
time_to_harvest = 4
time_to_replant = 120
effect_of_good_on_c_to_dev-p
GRAPH(fraction_good_new_development)
(0.02, 1.00), (0.118, 1.50), (0 .216, 2.05), (0.314,
2 .62), (0 .412,3.12), (0 .51,3.70), (0.608,4 .12),
(0.706, 4 .70), (0.804, 5 .20), (0.902, 5 .55), (1, 6 .00)
effect_of_stock_loss_on_good-practice =
GRAPH (stock_loss_fraction)
(0.025, 0.02), (0 .0475 , 0.182), (0.07, 0.309), (0.0925,
0 .397), (0.115, 0 .485) , (0.137, 0.603), (0 .16, 0.657),
(0.182,0.696), (0.205,0.74), (0.227,0.76), (0 .25,
0 .8)
effect_of_undev_ha_on_cost =
GRAPH (current_to_initial_undev_ha)
(0.00, 10 .0), (0.1, 6 .85), (0.2, 4.96), (0.3, 3.56),
(0.4,2.58), (0 .5,1.90), (0 .6,1.45), (0 .7,1.23),
(0.8, 1.14), (0 .9, 1.09), (1, 1.00)
Environment
Bad_Practice(t) = Bad_Practice(t-dt) +
(gaining_bad-ponds + becoming_bad-abandoning_bad-pondsbecoming_good) * dt
INIT Bad_Practice
Hectares_of_Ponds*.9
INFLOWS :
fraction_good_new_development))additional_good-practice
becoming_bad = 0
OUTFLOWS:
abandoning_bad-ponds = Bad_Practice/time_to_abandon_bad
becoming_good = MAX(ha_converted_to_good,O)