Create pie charts showing functional group composition

Visualise the relative proportion of plankton functional groups averaged across all samples. Useful for summarising community composition in a simple, accessible format.

pr_plot_PieFG(df)

Arguments

df

A dataframe from pr_get_FuncGroups() containing functional group abundance or biomass data

Value

A ggplot2 object that can be further customised or saved with ggsave()

Details

Plot Structure

The pie chart shows:

• Each functional group as a wedge

• Wedge size proportional to mean abundance/biomass across all samples

• Colours from the "Set1" palette for clear distinction

• Legend below plot listing all functional groups

Interpretation

This plot provides a quick overview of which functional groups dominate the plankton community on average. Use this for:

• Initial data exploration

• Comparing overall community structure between surveys or regions

• Educational presentations requiring simple visualisations

Limitations

• Shows average composition only, hiding temporal variability

• Cannot show changes over time (use pr_plot_tsfg() for that)

• Works best with 5-10 functional groups; too many makes wedges hard to distinguish

Functional Groups

The plot automatically detects whether data are:

• Phytoplankton: Diatoms, dinoflagellates, ciliates, etc.

• Zooplankton: Copepods, appendicularians, fish larvae, etc.

And labels the legend accordingly.

See also

• pr_get_FuncGroups() to generate input data

• pr_plot_tsfg() for time series of functional group composition

Examples

# Phytoplankton functional groups from CPR
df <- pr_get_FuncGroups("CPR", "Phytoplankton")
plot <- pr_plot_PieFG(df)
print(plot)


# Zooplankton functional groups from NRS
df <- pr_get_FuncGroups("NRS", "Zooplankton")
pr_plot_PieFG(df)


# Save to file
df <- pr_get_FuncGroups("CPR", "Zooplankton")
p <- pr_plot_PieFG(df)
ggplot2::ggsave("functional_groups_pie.png", p, width = 8, height = 6)