spatial_nutrient: Spatialize nutrient fertilization plans
In mbask/fertplanspatial: Compute And Spatialize NPK Fertilization Plans

Description Usage Arguments Details Value

View source: R/spatial_nutrient.R

Spatialization is performed bny fitting a variogram model to the nutrients fertilization plans and then performing ordinary kriging.

spatial_nutrient(
  sp_df,
  model = "auto",
  grid_spdf = NULL,
  bbox_buffer = 0L,
  spat_res = 5L,
  nutrient = "all",
  ...
)

`sp_df`	a Spatial soil nutrients fertilization dataset
`model`	a character vector describing the variogram model type. Either "auto" or one of the available variogram models to `gstat::vgm()`, e.g. "Exp", "Sph", "Gau", "Mat". Specific model parameters may be passed to `gstat::vgm()` as named function arguments arguments. In "auto" the optimal variogram is chosen by `automap::autofitVariogram()`. Calling gstat::vgm() without a model argument returns a data.frame with available models.
`grid_spdf`	a `sp::SpatialPoints()` object grid with nutrient predictions locations. If `NULL` (default) then a point grid is built using `sp_df` bounding box and coordinate reference system, each point spatially distant by `spat_res`.
`bbox_buffer`	an integer value to enlarge (or shrink) the bounding box the default point grid is built in (i.e. when grid_spdf is set to `NULL`). Default to `0L`, i.e. no effect on the bounding box.
`spat_res`	a positive number indicating the spatial resolution of the resulting spatial grid when `grid_spdf` is `NULL`. Default is 5 metres.
`nutrient`	a character vector detailing which nutrient spatialized fertilization plan to compute among "nitrogen", "phosphorus", and "potassium". Any combination of the three nutrients can be given or "all" (default) to compute all of them.
`...`	arguments that will be passed to `gstat::vgm()` or `automap::autofitVariogram()`

The function returns a list of sp::SpatialPointsDataFrame() grids on the bounding box of the spatial soil nutrients fertilization dataset, as returned by demand_nutrient(). Each spatial grid can be readily plotted or rasterized.

Spatial coordinates must be passed as 'X' and 'Y' named columns in sp_df spatial table. This table should also containing either 'nitrogen', 'phosphorus', and 'potassium' named columns according to the nutrient plan to be spatialized passed as nutrient argument.

a list with as many elements as nutrients given as nutrient parameter. Each element is a sp::SpatialPointsDataFrame().

mbask/fertplanspatial documentation built on July 5, 2020, 9:51 a.m.