spwb_spatial: Simulations for spatially-distributed forest stands

In emf-creaf/medfateland: Mediterranean Landscape Simulation

Simulations for spatially-distributed forest stands

Description

Functions that allow calling local models spwb, growth or fordyn, for a set of forest stands distributed in specific locations. No spatial processes are simulated.

Usage

spwb_spatial(
  sf,
  SpParams,
  meteo = NULL,
  local_control = defaultControl(),
  dates = NULL,
  CO2ByYear = numeric(0),
  keep_results = TRUE,
  summary_function = NULL,
  summary_arguments = NULL,
  parallelize = FALSE,
  num_cores = detectCores() - 1,
  chunk_size = NULL,
  progress = TRUE,
  local_verbose = FALSE
)

growth_spatial(
  sf,
  SpParams,
  meteo = NULL,
  local_control = defaultControl(),
  dates = NULL,
  CO2ByYear = numeric(0),
  fire_regime = NULL,
  keep_results = TRUE,
  summary_function = NULL,
  summary_arguments = NULL,
  parallelize = FALSE,
  num_cores = detectCores() - 1,
  chunk_size = NULL,
  progress = TRUE,
  local_verbose = FALSE
)

fordyn_spatial(
  sf,
  SpParams,
  meteo = NULL,
  local_control = defaultControl(),
  dates = NULL,
  CO2ByYear = numeric(0),
  fire_regime = NULL,
  keep_results = TRUE,
  management_function = NULL,
  summary_function = NULL,
  summary_arguments = NULL,
  parallelize = FALSE,
  num_cores = detectCores() - 1,
  chunk_size = NULL,
  progress = TRUE,
  local_verbose = FALSE
)

Arguments

sf	An object of class sf with the following columns: geometry: Spatial geometry. id: Stand identifiers. elevation: Elevation above sea level (in m). slope: Slope (in degrees). aspect: Aspect (in degrees). land_cover_type: Land cover type of each grid cell (values should be 'wildland' or 'agriculture'). forest: Objects of class forest. soil: Objects of class soil or data frames of physical properties. state: Objects of class spwbInput or growthInput (optional). meteo: Data frames with weather data (required if parameter meteo = NULL). crop_factor: Crop evapo-transpiration factor. Only required for 'agriculture' land cover type. local_control: A list of control parameters (optional). Used to override function parameter local_control for specific locations (values can be NULL for the remaining ones). management_arguments: Lists with management arguments. Optional, relevant for fordyn_spatial only. represented_area_ha: Area represented by each stand in hectares. Optional, relevant for fordyn_spatial when fire_regime is supplied only). ignition_weights: Relative weights to determine stands to be burned. Optional, relevant for fordyn_spatial when fire_regime is supplied only).
SpParams	A data frame with species parameters (see SpParamsMED).
meteo	Input meteorological data (see section details). If NULL, the function will expect a column 'meteo' in parameter y.
local_control	A list of control parameters (see defaultControl) for function spwb_day or growth_day.
dates	A Date object describing the days of the period to be modeled.
CO2ByYear	A named numeric vector with years as names and atmospheric CO2 concentration (in ppm) as values. Used to specify annual changes in CO2 concentration along the simulation (as an alternative to specifying daily values in meteo).
keep_results	Boolean flag to indicate that point/cell simulation results are to be returned (set to FALSE and use summary functions for large data sets).
summary_function	An appropriate function to calculate summaries (e.g., summary.spwb).
summary_arguments	List with additional arguments for the summary function.
parallelize	Boolean flag to try parallelization (will use all clusters minus one).
num_cores	Integer with the number of cores to be used for parallel computation.
chunk_size	Integer indicating the size of chuncks to be sent to different processes (by default, the number of spatial elements divided by the number of cores).
progress	Boolean flag to display progress information of simulations.
local_verbose	Boolean flag to display detailed progress information in local simulations.
fire_regime	A list of parameters defining the fire regime (see create_fire_regime) or a matrix representing a fire regime instance (see fire_regime_instance), to be used in simulations with fordyn_spatial. If NULL, wildfires are not simulated.
management_function	A function that implements forest management actions (see fordyn). of such lists, one per spatial unit.

Details

Simulation functions accept different formats for meteorological input (parameter meteo). The user may supply two kinds of daily weather sources:

1. A data frame with meteorological data common for all spatial location (spatial variation of weather not considered).

2. An object or (a list of objects) of class stars with reference interpolation data created by package meteoland. If a list of such interpolator objects is supplied, the simulation functions will interpolate on the target locations for the periods covered by each interpolator, but the user will be responsible for supplying interpolators in the correct temporal order.

Alternatively, the user may leave parameter meteo = NULL and specify a weather data frame for each element of y in a column named 'meteo'.

Fire regimes are only allowed for function fordyn_spatial. If an object of class fire_regime is supplied, the function will call fire_regime_instance to generate a realization of the fire regime before conducting simulations. Alternatively, users can directly supply a fire regime instance matrix, derived from another source (e.g. a fire landscape model). Note that operating with fire regimes assumes all forest stands share the same period of simulation, but enforcing this is left to the user.

Value

An object of class 'sf' containing four elements:

• geometry: Spatial geometry.

• id: Stand id, taken from the input.

• state: A list of spwbInput or growthInput objects for each simulated stand, to be used in subsequent simulations (see update_landscape) or with NULL values whenever simulation errors occurred.

• forest: A list of forest objects for each simulated stand (only in function fordyn_spatial), to be used in subsequent simulations (see update_landscape) or with NULL values whenever simulation errors occurred.

• management_arguments: A list of management arguments for each simulated stand (only in function fordyn_spatial if management function was supplied), to be used in subsequent simulations (see update_landscape).

• result: A list of model output for each simulated stand. Some elements can contain an error condition if the simulation resulted in an error. Values will be NULL (or errors) if keep_results = FALSE.

• summary: A list of model output summaries for each simulated stand (if summary_function was not NULL), with NULL values whenever simulation errors occurred.

Author(s)

Miquel De Cáceres Ainsa, CREAF

See Also

spwb, growth, fordyn, spwb_spatial_day, simulation_summary , plot_summary, initialize_landscape, update_landscape

Examples

# Load example landscape data
data("example_ifn")
  
# Load example meteo data frame from package meteoland
data("examplemeteo")
  
# Load default medfate parameters
data("SpParamsMED")
  
# Subset two plots to speed-up calculations
example_subset <- example_ifn[31:32, ]

# Perform simulation
dates <- seq(as.Date("2001-03-01"), as.Date("2001-03-15"), by="day")
res <- spwb_spatial(example_subset, SpParamsMED, examplemeteo, dates = dates)
  
# Perform fordyn simulation for one year (one stand) without management
res_noman <- fordyn_spatial(example_subset, SpParamsMED, examplemeteo)

emf-creaf/medfateland documentation built on April 17, 2025, 5:43 a.m.