sgf.area {CTFS} | R Documentation

## Number of Species, Genera and Families for a single defined Area

### Description

Counts the number of species, genera and families of the individuals found in a given single defined area of a plot. There area is defined by x, y coordinates and can be of any size. This function is used by other species area functions.

### Usage

    sgf.area(census1, spp.info, corners = c(0, 1000, 0, 500),
            alivecode = c("A"), mindbh = NULL, unidennames = c("**", "UNID", "uniden", "UNIDEN"))

### Arguments

`census1` | name of the datafame of a single census
`spp.info` | name of dataframe that contains each species and information about it, eg. `bcispp.info`
`corners` | x, y coordinates, in pairs of the corners of the area of the plot to be included
`alivecode` | character, codes of the variable `status` that indicate the tree is alive. The most general valid categories are: "A" and "AB" and "AS". The default for this function is "A"
`mindbh` | Minimum DBH for inclusion in computation
`unidennames` | vector of codes for unidentified species, codes vary among sites and datasets

### Details

This is the base function for all of the other `sgf.*` functions. Given any coordinates, it subsets the dataset for trees within those coordinates and calculates the number of individuals, species, genera and families. `alivecode`, `mindbh` and `unidennames` control which trees are included.

Pay attention to the default values of `alivecode` and `mindbh`. Any tree with `alivecode` not equal to “A” has a `dbh` = NA and so will not contribute to the results of this computation. Setting `mindbh` to some value other than NULL will affect the trees that are included in the calculation. Use `mindbh` to select trees larger than 10 mm dbh. Use `alivecode` to select trees to be counted as being alive but have no `dbh` measurement.

All areas are squares. For other shapes use `spp.randarea.range`

### Value

Returns a vector of the following information for the defined area.

`n.ind` | number of individuals
`n.spp` | number of species
`n.gen` | number of genera
`n.fam` | number of families
`r.sppgen` | ratio of number of species to number of genera
`r.sppfam` | ratio of number of species to number of families
`r.genfam` | ratio of number of genera to number of families

### Author(s)

Rick Condit, Suzanne Lao and Pamela Hall

### See Also

`CTFS.diversity`

### Examples

    ## Not run:
    1. default use gives the total number of species, genera, families for
    a given census
    sgf.area(bci90.full,bcispp.info)

    2. for the first hectare
    sgf.area(bci90.full,bcispp.info,corners=c=(0,100,0,100))

    3. note the differences among values for alivecode and mindbh, keep
    track of the default settings for each

    sgf.area(bci90.full,bcispp.info,alivecode=c("A","AB","AS"))
    sgf.area(bci90.full,bcispp.info,mindbh=NULL)
    sgf.area(bci90.full,bcispp.info,alivecode=c("A","AB","AS"),mindbh=NULL)
    ## End(Not run)

[Package CTFS version 1.00 Index]