Compare habitat connectivity of a scenario against a baseline

Starts from habitat and barrier layers, rather than the connectivity objects compare_connectivity() takes. Give it a scenario habitat/barrier pair and a baseline habitat/barrier pair and it runs the full connectivity pipeline on each (via habitat_connectivity()) and compares them. interpatch_distance may be a vector, in which case the comparison is run once per distance and the per-distance results are stacked.

Usage

habitat_connectivity_comparison(
  habitat_scenario,
  barrier_scenario,
  habitat_baseline,
  barrier_baseline,
  species,
  interpatch_distance,
  scenario_name = NULL,
  verbose = TRUE
)

Arguments

habitat_scenario

Terra SpatRaster. The scenario habitat layer.

barrier_scenario

Terra SpatRaster. The scenario barrier layer.

habitat_baseline

Terra SpatRaster. The baseline habitat layer.

barrier_baseline

Terra SpatRaster. The baseline barrier layer.

species

Species name. E.g., "Superb Fairy Wren".

interpatch_distance

Numeric. The distance (in metres) at which habitat patches are considered connected. May be a scalar or a vector; a vector runs the comparison once per distance. See habitat_connectivity().

scenario_name

Character. An optional label for the scenario, for example "Bentley Project". Passed to compare_connectivity(), and appears in the scenario_name column on every row. Defaults to NULL, which gives NA.

verbose

Logical. Display progress messages (default: TRUE).

Value

A compare_connectivity object: a tibble with four rows (baseline, scenario, change, pct_change) per interpatch distance. A scalar interpatch_distance gives four rows; a length-3 vector gives twelve rows (four per distance). See compare_connectivity() for the columns.

Details

Change exactly one layer between baseline and scenario so the difference is attributable to a single variable. To assess a barrier change, pass the same habitat to both habitat_baseline and habitat_scenario; to assess a habitat change, pass the same barrier to both barrier_baseline and barrier_scenario. If both the habitat and the barrier differ the function aborts; if neither differs it warns (the scenario equals the baseline, so every change value is zero).

Note that this runs the full connectivity pipeline 2 * length(interpatch_distance) times (buffering is the slow step), so a long vector of distances will take proportionally longer.

See also

compare_connectivity(), habitat_connectivity()

Examples

# \donttest{
habitat_connectivity_comparison(
  habitat_scenario = example_wren_habitat(),
  barrier_scenario = example_wren_barrier_scenario(),
  habitat_baseline = example_wren_habitat(),
  barrier_baseline = example_wren_barrier(),
  species = "Superb Fairy Wren",
  interpatch_distance = 200,
  verbose = FALSE
)
#> # Connectivity comparison: baseline / scenario / change / pct_change
#> # A tibble: 4 × 10
#>   scenario_name measure    species           interpatch_distance n_patches
#>   <chr>         <chr>      <chr>                           <dbl>     <dbl>
#> 1 NA            baseline   Superb Fairy Wren                 200   282    
#> 2 NA            scenario   Superb Fairy Wren                 200   283    
#> 3 NA            change     Superb Fairy Wren                 200     1    
#> 4 NA            pct_change Superb Fairy Wren                 200     0.355
#>   effective_mesh_ha prob_connectedness patch_area_mean patch_area_total_ha
#>               <dbl>              <dbl>           <dbl>               <dbl>
#> 1           334.          0.0000225           52556.               1482.  
#> 2           333.          0.0000224           51828.               1467.  
#> 3            -0.965      -0.0000000651         -728.                -15.3 
#> 4            -0.289      -0.289                  -1.38               -1.04
#>   data_resolution 
#>   <chr>           
#> 1 9.99673x10.00151
#> 2 9.99673x10.00151
#> 3 9.99673x10.00151
#> 4 9.99673x10.00151
#> # change = scenario - baseline (positive = scenario is higher)
#> # pct_change = 100 * change / baseline
# }