SDI.Max: Plot Level Maximum Stand Density Function

In ryanmismith/inventoryfunctions: Forestry Inventory Functions

Plot Level Maximum Stand Density Function

Description

This function computes the Maximum Stand Density of each plot using one of two methods. If you include the necessary Climate Site Index data and plot coordinates (lat, long or a SpatialPointsDF) SDImax will be calculated using the Weiskittel and Kuehne method. If you fail to input this information SDImax will be calculated using Woodall's method based solely on mean standard gravity.

Usage

SDI.Max(
  Stand,
  Plot,
  Tree,
  SPP,
  DBH,
  EXPF,
  CSI = NULL,
  X_Coord = NULL,
  Y_Coord = NULL,
  project = NULL,
  SpatialPointsDF = NULL
)

Arguments

Stand	Unique Stand ID
Plot	Unique Plot ID
Tree	Unique Tree ID
SPP	Species observation for every tree (FVS species code)
EXPF	Expansion factor for each tree.
CSI	Climate site index for each tree.
X_Coord	Plot X coordinate for each tree
Y_Coord	Plot Y coordinate for each tree
project	The projection used for your provided coordinates will be EPSG:4326 unless another value is provided.
SpatialPointsDF	A SpatialPointsDF may be provided for the data instead of X and Y coords.

Details

Both methods in the description are proposed methods for obtaining Maximum Stand Density for uneven aged mixed stands. Please see references for further information. It is the recommendation of the author of this function that you utilize the Weiskittel method for calculating SDI.Max.

You can enter either a set of X and Y coordinates or a SpatialPointsDF into this function.

Value

The return a numeric vector of length n with the value of the maximum stand density per hectare. This function, along with SDI.Plot, is required to compute the relative density of a stand with RD.

Author(s)

Ryan Smith

References

Weiskittel, A. R., & Kuehne, C. (2019). Evaluating and modeling variation in site-level maximum carrying capacity of mixed-species forest stands in the Acadian Region of northeastern North America. The Forestry Chronicle, 95(03), 171–182. https://doi.org/10.5558/tfc2019-026

Woodall, C.W., P.D. Miles and J.S. Vissage. 2005. Determining maximum stand density index in mixed species stands for strategic- scale stocking assessments. For. Ecol. Manage. 216: 367–377.

See Also

SDI.Plot

RD

Other Stand Density Index Functions: RD(), SDI.Plot()

Other Plot Level Functions: BA.Larger.Trees(), BAPH(), CCF.Larger(), CrownCompF(), DBHFuns(), HeightPredict(), RD(), SDI.Plot(), TPH(), TallestTrees(), Unique.ID()

Examples

Stand <- c(1,1,1,1,1,1)
Plot  <- c(1,1,1,2,2,2)
Tree  <- c(1,2,3,1,2,3)
SPP   <- c("RO", "WP", "EH", "YB", "YB", "SM")
DBH <- c(42, 23, 61, 25, 55, 15)
EXPF <- c(866.1473, 2888.249, 410.6111, 2444.614, 505.0856, 6790.595)
SDI.Max(Stand, Plot, Tree, SPP, DBH, EXPF)

ryanmismith/inventoryfunctions documentation built on Aug. 5, 2022, 2:22 a.m.