abundance.spp {CTFS} | R Documentation

## Abundance of Trees by Species and DBH Classes

### Description

Computes the number of trees for each species and each DBH class. DBH classes can be user defined. The dataset may have 1 or more censuses but only 1 census is used by this function. See details for how the variables should be named.

### Usage

    abundance.spp(census1, alivecode=c("A"), dbhclass=c(10,100,300))

### Arguments

`census1` | name of census datafile for a single census
`alivecode` | character, codes of the variable `status` that indicate the tree is alive. Valid categories are: "A" and "AB" and "AS".
`dbhclass` | lower class boundaries for DBH classes, classes are nonoverlapping

### Details

This function returns the same values as `\list{abundance}` using species and dbh classes as the split variables.

See `CTFS.abundance` for details on the computation methods of abundance and associated functions. Values for only 1 census can be computed at a time.

A tree is included for the computation based on its value for `status` and `dbh` for a single census.

### Value

`abundance.spp`returns a list of arrays with the values of species as the first dimension and the values of dbh category as the second dimension of the array. The array contains the following named components:

`$N` | the abundance of each category, population size
`$dbhmean` | the mean dbh in mm for trees used to compute abundance
`$meandate` | mean date of census for trees used to compute abundance

The first array of the returned list is a matrix of the abundance of each species by dbh class. Abundance values are returned for all levels of each vector and if no value can be computed then 0 or NA is returned as appropriate.

### Author(s)

Rick Condit, Suzanne Lao and Pamela Hall

### See Also

`CTFS.abundance`

### Examples

    ## Not run:
    # 1. Default use of abundance.spp
    abund.sp.out <- abundance.spp(tst.bci90.full)
    abund.sp.out[[1]]

    # 2. Using different dbh classes
    abund.sp.out1 <-
    abundance.spp(tst.bci90.full,dbhclass=c(100,200,300,400,500))

    ## End(Not run)

[Package CTFS version 1.00 Index]