TIM Version 3.0 beta Technical Description and User Guide - Appendix C -Parameters used in TIM v3.0
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Symbol |
Definition |
Variable Type* |
Units |
---|---|---|---|
A |
Area of home range |
Random |
m^{2} |
AE_{k} |
Assimilation efficiency for food item k |
Random |
none |
A_{rate} |
Application rate of pesticide |
Constant |
lb a.i./A |
B |
Length of in-field spray drift buffer |
Constant |
m |
B_{vol} |
Volume-based biotransfer factor; function of Henry’s law constant and Log Kow |
Constant |
µg/L fresh weight leaf/ μg/L air |
BW |
Body weight |
Random |
g/bird |
C_{air(t)(drops)} |
Pesticide concentration in a volume of air for the time step immediately following the pesticide application |
Constant |
μg/mL |
C_{air(t)(vol)} |
Concentration of the pesticide in air at time t (resulting from volatilization) |
Random |
μg/mL |
CH |
Height of crop |
Constant |
m |
C_{k(t)} |
Pesticide concentration on food item k at time t |
Random |
μg pesticide/g food |
C_{k(t=0)} |
Starting residue concentration on the day of application |
Random |
μg pesticide/g food |
C_{plant(t)} |
Concentration of the pesticide in crop foliage at time t |
Random |
mg/kg |
C_{w(dew)(t)} |
Concentration of dissolved pesticide in dew at time t |
Random |
μg/mL |
C_{w(puddle)(t)} |
Concentration of the pesticide in puddle at time t |
Random |
μg/mL |
D |
Fraction of hour where pesticide is applied |
Constant |
none |
d |
length of home range |
Random |
m |
d1 |
portion of d that overlaps with the treated field |
Random |
m |
d2 |
portion of d that is off of the treated field |
Random |
m |
d3 |
distance between edge of treated field and edge of home range (that does not overlap with treated field) |
Random |
m |
DAF |
Dermal absorption fraction |
Constant |
none |
D_{contact(t)} |
Incidental Dermal Contact Dose |
Random |
μg pesticide/g-bw |
D_{dermal(t)} |
Dose through dermal exposure for a pesticide at time t |
Random |
μg pesticide/g-bw |
D_{dew(t)} |
Dose through drinking dew for a pesticide at time t |
Random |
μg pesticide/g-bw |
D_{diet(t)} |
Dose through diet for a pesticide at time t |
Random |
μg pesticide/g-bw |
D_{drinking(t)} |
Dose through drinking water for a pesticide at time t |
Random |
μg pesticide/g-bw |
DF_{k} |
Fraction of diet attributed to food item k |
Constant |
none |
D_{inhalation(t)} |
Dose through inhalation for a pesticide at time t |
Random |
μg pesticide/g-bw |
D_{intercept(t)} |
Intercepted Dermal Dose |
Random |
μg pesticide/g-bw |
d_{non-feeding} |
location of bird during non-feeding hours relative to edge of treated field |
Random |
m |
DPR |
Dislodgeable pesticide residues |
Constant |
mg/m^{2} |
d_{soil} |
Depth of soil at equilibrium with water (in puddle) |
Constant |
cm |
D_{spray(t)} |
Droplet Inhalation Dose |
Random |
μg pesticide/g-bw |
dt |
distance from edge of field at time t |
Random |
m |
D_{total(t)} |
Dose from all exposure routes |
Random |
μg pesticide/g-bw |
D_{vapor(t)} |
Volatilization inhalation dose; function of pesticide concentration in air, volume of inhaled air, and body weight of the bird |
Random |
μg pesticide/g-bw |
d_{w} |
Depth of puddle water |
Random |
cm |
DWIR |
Drinking water intake rate |
Random |
mL/day |
e |
Base of natural logarithm (2.7182) |
Constant |
none |
EEC_{diet(t)} |
Estimated exposure concentration through diet for a pesticide at time t |
Random |
μg pesticide/g-bw |
F_{AM} |
Ratio of avian to mammalian pulmonary membrane diffusion rates from USEPA 2004 |
Constant |
none |
FC_{k} |
Fraction of food that is contaminated |
Constant |
none |
F_{dfr} |
Dislodgeable foliar residue adjustment factor |
Constant |
kg/m^{2} |
F_{field} |
Fraction of on field exposure |
Random |
none |
FLUX_{water} |
Total daily water ingestion rate |
Random |
mL/day |
FMA |
Food matrix adjustment factor |
Constant |
none |
FMR |
Free-living metabolic rate |
Random |
kcal/bird-day |
f_{oc(soil)} |
Fraction of organic carbon in soil |
Constant |
none |
FOF |
Frequency on field |
Random |
none |
F_{re} |
Avian route equivalency factor |
Constant |
none |
F_{red} |
dermal route equivalency factor |
Constant |
none |
F_{respired} |
Volumetric fraction of droplet spectrum not exceeding the upper size limit of respired particles for birds |
Constant |
none |
F_{retained} |
Fraction of pesticide that is retained in the bird from one time step to the next |
Constant |
none |
FW_{k} |
Fraction of water in fresh food item k |
Constant |
None |
G |
Gorging factor |
Constant |
None |
GE_{k} |
Gross energy for food item k |
Random |
kcal/g food |
H |
Henry’s law constant |
Constant |
atm/m^{3}/mol |
HF_{(t)} |
Hourly fraction of total daily intake rate of food consumed at time t |
Random |
none |
k |
Food item |
Constant |
none |
Koc |
Organic carbon-water partition coefficient |
Constant |
mL/g OC |
Kow |
Octanol-water partition coefficient |
Constant |
none |
LD_{50} |
Lethal dose sufficient to kill 50% of exposed individuals |
Constant |
mg/kg |
m_{wax} |
Amount of wax per surface area of leaf cuticle |
Constant |
Ug/cm2 |
ME_{k} |
Metabolizable energy for food item k |
Random |
kcal/g food |
ME_{total} |
Total metabolizable energy |
Random |
kcal/g food |
M_{pesticide} |
Pesticide concentration on the treated field at time t (accounting for dissipation); function of application rate |
Random |
mg |
m_{plant} |
Mass of plant per hectare |
Constant |
kg |
m_{wax} |
mass of wax per surface area of leaf cuticle |
Constant |
μg/cm^{2} |
n |
Flock size |
Constant |
none |
P_{00} |
Probability that a bird, now off the field, will remain off the field in the next hour |
Random |
none |
P_{01} |
Probability that a bird, now off the field, will be on the field in the next hour |
Random |
none |
P_{10} |
Probability that a bird, now on the field, will be off the field in the next hour |
Random |
none |
P_{11} |
Probability that a bird, now on the field, will be on the field in the next hour |
Random |
none |
P(x) |
Probability of mortality to x birds |
Constant |
none |
p |
Fraction of total birds that died during simulation |
Constant |
none |
Q |
Fidelity factor |
Constant |
none |
R |
Universal gas constant (8.205 e^{-5}) |
Constant |
atm/m^{3}/mol-K |
r |
degredation rate constant |
Constant |
hour^{-1} |
R_{foliar contact} |
Rate of foliar contact |
Constant |
cm^{2}foliage/cm^{2}body surface (per hour) |
RH |
height of spray release |
Constant |
m |
r_{k} |
Pesticide specific dissipation rate constant (for food item k) |
Constant |
hour^{-1} |
R_{rate} |
Respiration rate |
Random |
L/h |
s |
Mineau scaling factor |
Constant |
none |
SA_{total} |
Total surface area of bird |
Random |
cm^{2} |
S_{F} |
Food ingestion scale factor |
Random |
none |
S_{I} |
Inhalation scale factor |
Random |
none |
S_{W} |
Water adjustment scale factor |
Random |
none |
T |
Air temperature |
Constant |
K |
t |
Time of simulation |
Sequential value |
hour |
t_{1/2k} |
Dissipation half-life for food item k |
Constant |
days |
TDIR |
Total daily intake rate |
Random |
g food/bird-day |
T_{mortality} |
Individual threshold for mortality |
Random |
μg pesticide/g-bw |
TPR |
Total pesticide residues |
Constant |
mg/kg |
V_{air} |
Volume of air in 1 ha to a height equal to the height of the crop canopy |
Constant |
L |
V_{inhalation} |
Volume of air respired |
Random |
L |
water_{food} |
Daily volume of water consumed by a bird through food |
Random |
mL/day |
x |
Number of dead birds (out of predetermined flock); used to determine probability |
Constant |
none |
ε_{t} |
Presence on-field, off-field parameter |
Random |
none |
θ_{soil} |
Porosity of soil |
Constant |
none |
ρ_{b} |
Bulk density of soil |
Random |
kg/L |
ρ_{p} |
density of soil particles |
Constant |
kg/L |
ρ_{water} |
density of water (1) |
Constant |
kg/L |
ρ_{plant} |
Density of the crop tissue assumed as fresh leaf |
Constant |
kg/L |
^{*} "Constant" indicates that the parameter is set to one value. "Random" indicates that the parameter’s value varies based on a distribution of possible values.