apply_height_eq: Apply height equation

In SilviaTerra/rpnc250: R implentation of USFS Research Paper NC-250: Tree Volume and Biomass Equations for the Lake States

Apply height equation

Description

Apply the height equation (eq. 2 in publication) from RP NC-250 using provided dbh, site index, outside-bark top diameter, stand basal area, and coefficients from Table 1 in the publication.

Usage

apply_height_eq(
  dbh,
  site_index,
  top_dob,
  stand_basal_area,
  b1,
  b2,
  b3,
  b4,
  b5,
  b6
)

Arguments

dbh	vector of DBH observations in inches
site_index	vector of site index estimates (base age 50)
top_dob	vector of outside-bark diameter values to which height will be estimated
stand_basal_area	vector of stand-level basal area estimates corresponding to the stems
b1, b2, b3, b4, b5, b6	numeric vector of model coefficients from Table 1

Details

The height equation is as follows:

Height = 4.5 + b_1(1-e^{(-b_2D)})^{b_3}*S^{b_4}*T^{b_5}*B^{b_6}

Where:

• b_1, b_2, b_3, b_4, b_5, b_6 are species specific coefficients from Table 1

• D is diameter at breast height in inches

• S is site index (base age 50)

• T is 1.00001 - d/D, d is top diameter outside bark

• B is stand basal area in square feet per acre

Value

vector of height estimates

Examples

## Not run: 
apply_height_eq(
  dbh = 10,
  site_index = 60,
  top_dob = 4,
  stand_basal_area = 75,
  b1 = table1$b1[1],
  b2 = table1$b2[1],
  b3 = table1$b3[1],
  b4 = table1$b4[1],
  b5 = table1$b5[1],
  b6 = table1$b6[1]
)

## End(Not run)

SilviaTerra/rpnc250 documentation built on March 28, 2023, 12:45 a.m.