Calculate predicted environmental concentrations in surface water due to drift

This is a basic, vectorised form of a simple calculation of a contaminant concentration in surface water based on complete, instantaneous mixing with input via spray drift.

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Usage

>>>>>>> refs/remotes/origin/main

PEC_sw_drift(
  rate,
  applications = 1,
  water_depth = 30,
  drift_percentages = NULL,
  drift_data = c("JKI", "RF"),
  crop = "Ackerbau",
  distances = c(1, 5, 10, 20),
  rate_units = "g/ha",
  PEC_units = "µg/L"
)

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Arguments

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Arguments

>>>>>>> refs/remotes/origin/main

rate: Application rate in units specified below
applications: Number of applications for selection of drift percentile
water_depth: Depth of the water body in cm
drift_percentages: Percentage drift values for which to calculate PECsw. 'drift_data' and 'distances' if not NULL.
drift_data: Source of drift percentage data. If 'JKI', the [drift_data_JKI] =======; Source of drift percentage data. If 'JKI', the drift_data_JKI >>>>>>> refs/remotes/origin/main included in the package is used. If 'RF', the Rautmann formula is used, if implemented for the crop type and number of applications
crop: Crop name (use German names for JKI data), defaults to "Ackerbau"
distances: The distances in m for which to get PEC values
rate_units: Defaults to g/ha
PEC_units: Requested units for the calculated PEC. Only µg/L currently supported

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Value

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Value

>>>>>>> refs/remotes/origin/main

The predicted concentration in surface water

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Author

Johannes Ranke

Examples

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Author

Johannes Ranke

Examples

>>>>>>> refs/remotes/origin/main

PEC_sw_drift(100)
#>        1 m        5 m       10 m       20 m 
#> 0.92333333 0.19000000 0.09666667 0.05000000 
# Alternatively, we can use the formula for a single application to "Ackerbau" from the paper
PEC_sw_drift(100, drift_data = "RF")
#>        1 m        5 m       10 m       20 m 
#> 0.92350000 0.19114149 0.09699222 0.04921742 

# This makes it possible to also use different substances
PEC_sw_drift(100, distances = c(1, 3, 5, 6, 10, 20, 50, 100), drift_data = "RF")
#>        1 m        3 m        5 m        6 m       10 m       20 m       50 m 
#> 0.92350000 0.31512171 0.19114149 0.15990435 0.09699222 0.04921742 0.02007497 
#>      100 m 
#> 0.01018678 

# Using custom drift percentages is also supported
PEC_sw_drift(100, drift_percentages = c(2.77, 0.95, 0.57, 0.48, 0.29, 0.15, 0.06, 0.03))
#>     2.77 %     0.95 %     0.57 %     0.48 %     0.29 %     0.15 %     0.06 % 
#> 0.92333333 0.31666667 0.19000000 0.16000000 0.09666667 0.05000000 0.02000000 
#>     0.03 % 
#> 0.01000000

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