R/Brandel_1990.R

In Silviculturalist/forester: Forest Science and Forestry

#' Brandel 1990 Volume for Birch
#'
#' @description Volume functions for Birch which are used in Heureka. PM Heureka 2004-01-20 Björn Elfving.
#'
#' @source Brandel, G. 1990. Volymfunktioner för enskilda träd. Tall, gran och björk. SLU, inst. för skogsproduktion. Rapport nr 26.
#'
#'
#' @source Available: \url{https://www.heurekaslu.org/w/images/9/93/Heureka_prognossystem_\%28Elfving_rapportutkast\%29.pdf}
#'
#' @param diameter_cm Diameter in cm
#' @param height_m Height, metres.
#' @param latitude Latitude
#'
#' @return Volume, in dm3.
#' @export
Brandel_1990_volume_Birch <- function(
  diameter_cm,
  height_m,
  latitude
){
  ifelse(latitude>60,
         return(
           10^(

             	-0.44224 + 	2.47580*log10(diameter_cm)	-1.40854*log10(diameter_cm+20) +	5.16863*log10(height_m)	-3.77147*log10(height_m-1.3)
           )
         ),
         return(
           10^(

            	-0.89359 +	2.27954*log10(diameter_cm) +		-1.18672*log10(diameter_cm+20) +	7.07362*log10(height_m)	-5.45175*log10(height_m-1.3)
           )
         )
  )
}
#' Brandel 1990 Volume for Scots Pine
#'
#' @description Volume functions for Scots Pine which are used in Heureka. PM Heureka 2004-01-20 Björn Elfving.
#'
#' @source Brandel, G. 1990. Volymfunktioner för enskilda träd. Tall, gran och björk. SLU, inst. för skogsproduktion. Rapport nr 26.
#'
#'
#' @source Available: \url{https://www.heurekaslu.org/w/images/9/93/Heureka_prognossystem_\%28Elfving_rapportutkast\%29.pdf}
#'
#' @param diameter_cm Diameter in cm
#' @param height_m Height, metres.
#' @param latitude Latitude
#'
#' @return Volume, in dm3.
#' @export
Brandel_1990_volume_Pine <- function(
  diameter_cm,
  height_m,
  latitude
){
  ifelse(latitude>60,
  return(
    10^(
      -1.20914 + 	1.94740*log10(diameter_cm)	-0.05947*log10(diameter_cm+20) +	1.40958*log10(height_m)	-0.45810*log10(height_m-1.3)
    )
  ),
  return(
    10^(
      -1.38903 +1.84493*log10(diameter_cm) +	0.06563*log10(diameter_cm+20) +	2.02122*log10(height_m)	-1.01095*log10(height_m-1.3)
    )
  )
  )
}
#' Brandel 1990 Volume for Norway Spruce
#'
#' @description Volume functions for Norway Spruce which are used in Heureka. PM Heureka 2004-01-20 Björn Elfving.
#'
#' @source Brandel, G. 1990. Volymfunktioner för enskilda träd. Tall, gran och björk. SLU, inst. för skogsproduktion. Rapport nr 26.
#'
#'
#' @source Available: \url{https://www.heurekaslu.org/w/images/9/93/Heureka_prognossystem_\%28Elfving_rapportutkast\%29.pdf}
#'
#' @param diameter_cm Diameter in cm
#' @param height_m Height, metres.
#' @param latitude Latitude
#'
#' @return Volume, in dm3.
#' @export
Brandel_1990_volume_Spruce <- function(
  diameter_cm,
  height_m,
  latitude
){
  ifelse(latitude>60,
         return(
           10^(

             	-0.79783 + 	2.07157*log10(diameter_cm)	-0.73882*log10(diameter_cm+20) +	3.16332*log10(height_m)	-1.82622*log10(height_m-1.3)
           )
         ),
         return(
           10^(

             	-1.02039 +2.00128*log10(diameter_cm) +	-0.47473*log10(diameter_cm+20) +	2.87138*log10(height_m)	-1.61803*log10(height_m-1.3)
           )
         )
  )
}