medfateland (version 2.8.1)

create_management_scenario: Create management scenario

Description

Defines a management scenario for simulations of forest dynamics

Usage

create_management_scenario(
  units,
  annual_demand_by_species = NULL,
  extraction_rate_by_year = NULL,
  default_management_arguments = NULL
)

Value

A list with the following structure:

• scenario_type: Either 'bottom-up' (no demand is specified), 'input_demand' (annual species demand is specified), or 'input_rate' when extraction rates are also supplied.

• annual_demand_by_species: A vector of annual wood demand (m3) by species (or species groups) (for scenario_type 'bottom-up' or 'input_demand').

• extraction_rate_by_year: A vector of extraction rate values per year.

• units: A data frame with as many rows as units and management arguments as columns.

Arguments

units

Number of management units. Alternatively, a data frame with management options (in columns) for a set of units (in rows). Options not specified witl be taken from defaults.

annual_demand_by_species

A vector or matrix of annual wood demand (m3) by medfate species names (or groups of species names). If empty, the scenario is 'bottom-up' (not based on demand). If a vector is supplied, the same wood demand is applied for all simulated years. If a matrix is supplied, each row should correspond to a different year.

extraction_rate_by_year

A vector of extraction rates (%) per year of the simulation, starting at the second year. If specified, the annual demand by species will be applied for the first year of the simulation, but it will be rescaled for the remaining years according to the growth observed and the desired extraction rates.

default_management_arguments

A list of arguments to be passed to the managementFunction. These arguments will be taken as defaults copied for all management units and can later be modified. If NULL, the result of calling function defaultManagementArguments will be taken.

Author

Miquel De Cáceres Ainsa, CREAF

Aitor Améztegui, UdL

Details

Three kinds of management scenarios are allowed:

1. 'bottom-up' represents a scenario where forest stands belong to different management units, each of them having possibly distinct management prescriptions. However, there is no demand and the amount of extracted wood emerges from the interplay between forest dynamics and management prescriptions.

2. 'input_demand' represents a scenario where a certain amount of wood extraction is targeted for some species and each year. This requires deciding which stands will actually undergo thinning operations to fulfill the demand (stands managed following prescriptions that indicate final regeneration cuts are managed irrespective of demand).

3. 'input_rate' represents a scenario similar to the previous one but where total amount of wood targeted depends on (i.e. is a proportion of) the growth observed in previous year.

The kind of management scenario depends on the arguments supplied by the user when calling create_management_scenario (see examples). In all cases, management units need to be defined. Each management unit represents a group of forest stands following the same management prescriptions. Although the create_management_scenario function allows specifying the management arguments of each unit, the simulation of management scenarios also requires specifying, for each forest stand, to which management unit it belongs (see fordyn_scenario).

See Also

fordyn_scenario, defaultManagementFunction, defaultPrescriptionsBySpecies, create_fire_regime

Examples

# A scenario with three management units and annual demand for two species
scen_1 <- create_management_scenario(3,  c("Quercus ilex" = 1000, "Pinus nigra" = 2000))

# A scenario like the former, but with total annual demand changing as a function of
# prescribed extraction rates (second and third years)
scen_2 <- create_management_scenario(3,  
           c("Quercus ilex" = 1000, "Pinus nigra" = 2000),
           c("2002" = 30, "2003" = 50))
        
# A scenario with as many management units as rows in 'defaultPrescriptionsBySpecies'
# and not based on demand
data("defaultPrescriptionsBySpecies")
scen_3 <- create_management_scenario(defaultPrescriptionsBySpecies)

# A scenario with three management units and annual demand for one species group 
# and a third species
scen_4 <- create_management_scenario(3,  c("Quercus ilex/Quercus pubescens" = 1000, 
                                           "Pinus nigra" = 2000))