sgf.area {CTFS} | R Documentation |
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.
sgf.area(census1, spp.info, corners = c(0, 1000, 0, 500), alivecode = c("A"), mindbh = NULL, unidennames = c("**", "UNID", "uniden", "UNIDEN"))
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 |
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
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 |
Rick Condit, Suzanne Lao and Pamela Hall
## 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)