186
9. Modeling Eelgrass (Zostera marina L.) Distributions in Great Bay
Roots_length(t) = Roots_length(t-dt) + (Root_growthdiscarded_R&R") * dt
INIT Roots_length = 1
INFLOWS :
Root_growth = Rhiz_growth* .l
OUTFLOWS:
discarded_R&R" = Roots_length*Dyoff_rate
R&R_CHO_conc = (CHO_R&R) /R&R_volume
R&R_volume =
((Rhizome_Length*PI* .5
A 2 ) + ( R o o t s _ l e n g t h * P I * . l A2)) /1000
Dyoff_rate = GRAPH(Day)
(0.00, 0.00065), (33.2, 0.0007) , (66.4, 0.0014) , (99.5,
0 .00245), (133, 0.0043), (166, 0.0067), (199, 0.00745),
(232, 0.0065), (265, 0 .00385), (299, 0.0021), (332,
0 .00075), (365, 0 .00055)
shoot = CHO_shoot + youngest_leaves + young_leaves +
medium_leaves + old_leaves + older_leaves +
oldest_leaves
INFLOWS:
shoot_from_PSP =
(0 .4*Light /4)*Leaf_area*((oMax_Shoot_densitY*Nr_of_sho0
tsLeaf_area) /oMax_Shoot_densitY*Nr_of_shoots)*O.OOOOOOOl8
R&R_to_Shoot = RhizRoot_to_Shoot
OUTFLOWS:
Discarded_shoot = Discarded shoot' + Discarded_shoot" +
Discarded_shoot"' + Discarded_shoot""
Shoot_to_RhizRoot = Shoot to RhizRoot' 2
To_Reproductives = To_Reproductives'
CHO_shoot(t) = CHO_shoot(t -dt) + (shoot_from_PSP' +
R&R_to_Shoot'-L1_growth-L2_growth-L3_growth-L4_growthL5_growth-L6_growth-Shoot_to_RhizRoot '_2To_Reproductives'-New) * dt
INIT CHO_shoot
50 *Shoot_volume
INFLOWS:
shoot_from_PSP '
R&R_to_Shoot' =
= shoot_from_PSP
R&R_to_Shoot
OUTFLOWS:
L1_growth
L2_growth
youngest_leaves*L1_model
young_leaves*L2_model