Plot a Carlson TSI deviation diagram

ok_plot_tsi() produces a Carlson (1977) TSI deviation diagram, plotting TSI(TP) on the x-axis against TSI(Chl-a) and TSI(Secchi) on the y-axis with trophic state background bands. Deviations from the 1:1 line indicate light limitation (Chl-a below TP line) or non-algal turbidity (Secchi below Chl-a line).

Can accept either a single okBATHTUB result, or a data frame containing the required TSI columns (e.g. from ok_scenario() or a user-supplied observed-data summary).

Usage

ok_plot_tsi(x, color_by = NULL, lake_name = NULL, show_diagonal = TRUE)

Arguments

x

An okBATHTUB object, or a data frame containing columns tsi_tp, tsi_chla, and optionally tsi_secchi. If a data frame, it may also contain lake_name and eco_l3_name for grouping.

color_by

Character. Column name in a data frame to color points by. Common choices: "eco_l3_name", "trophic_state", "lake_name". Ignored when x is an okBATHTUB object.

lake_name

Character. Lake name for the plot title when x is an okBATHTUB object.

show_diagonal

Logical. Show the 1:1 reference line. Default TRUE.

Value

A ggplot2 object.

References

Carlson, R.E. (1977). A trophic state index for lakes. Limnology and Oceanography, 22(2), 361-369.

See also

ok_tsi, ok_tsi_observed

Examples

# \donttest{
# From a single pipeline result
result <- ok_load(inflow_m3yr = 45e6, tp_inflow_ugl = 120,
                   coefficients = "oklahoma",
                   ecoregion    = "Cross Timbers") |>
  ok_hydraulics(surface_area_ha = 890, mean_depth_m = 4.2) |>
  ok_retention() |>
  ok_inlake()    |>
  ok_tsi()
ok_plot_tsi(result, lake_name = "Arcadia Lake")

# }