Calculate the precipitation surplus

This function calculates the precipitation surplus (in mm / ha) given the crop rotation plan. Is identical to OBIC function calc_psp but much faster to facilitate national and regional calculations

Usage

bbwp_calc_psp(B_LU_BRP, M_GREEN, M_GREEN_START = 10L, M_GREEN_TERMINATE = 1L)

Arguments

B_LU_BRP

(numeric) The crop code from the BRP

M_GREEN

(boolean) A soil measure. Are catch crops sown after main crop (optional, options: TRUE, FALSE)

M_GREEN_START

(integer) Month in which the green manure is sown

M_GREEN_TERMINATE

(integer) Month in which the green manure is terminated

Value

The estimated precipitation surplus (in mm / ha) depending on averaged precipitation and evaporation. A numeric value.

Details

This function is calculates a precipitation surplus over 12 months taking green manures into account. The function does not take crop rotations or successive years into account. As such, including a winter cereal, which modifies evapotranspiration from January to August, does not alter the autumn evapotranspiration. If for example, a crop rotation includes potato followed by winter wheat, the year with potato cultivation should have M_GREEN = TRUE. The winter wheat acts as a green manure/catch crop for the potato's year.

Examples

bbwp_calc_psp(B_LU_BRP = 265, M_GREEN = TRUE)
#> [1] 209.475
bbwp_calc_psp(B_LU_BRP = c(265,1019,265,1019), M_GREEN = rep(TRUE,4))
#> [1] 209.475 279.155 209.475 279.155
bbwp_calc_psp(B_LU_BRP = c(2014, 2767), M_GREEN = rep(TRUE,2),
             M_GREEN_START = c(10L, 11L), M_GREEN_TERMINATE = c(12L, 3L))
#> [1] 415.911 567.678