sgf.meanarea {CTFS} | R Documentation |
Computes the mean and standard deviations of the number of species,
genera and families of the individuals for a given number of
relicates of randomly selected areas. There area is defined by
quaddim
with a randomly selected initial corner. It calls
sgf.area
to do the counting.
sgf.meanarea(census1, spp.info, quaddim = c(100, 100), alivecode = c("A"), mindbh = NULL, plotdim = c(1000, 500), replicates = 50, 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 |
quaddim |
dimensions (x,y) of the randomly selected area, in meters |
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 |
plotdim |
plot dimensions, x,y lengths, in meters |
replicates |
number of randomly selected areas to sample |
unidennames |
vector of codes for unidentified species, codes vary among sites and datasets |
The number of samples is determined by replicates
. Areas must
be rectangles but do not need to be squares. Only one area shape
and size is used in each function call. For a range of area types
and sizes use sgf.meanarea.range
.
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.
Returns a vector of the means and standard deviations of the following information.
mn.nind |
mean number of individuals |
sd.nind |
standard deviation of the number of individuals |
mn.nspp |
mean number of species |
sd.nspp |
standard deviation of the number of species |
mn.ngen |
mean number of genera |
sd.ngen |
standard deviation of the number of genera |
mn.nfam |
mean number of families |
sd.nfam |
standard deviation of the number of families |
mn.rsppgen |
mean of the ratio of number of species to number of genera |
sd.rsppgen |
standard deviation of the ratio of the number of species to number of genera |
mn.rsppfam |
mean of the ratio of number of species to number of family |
sd.rsppfam |
standard deviation of the ratio of the number of species to number of family |
mn.rgenspp |
mean of the ratio of number of genera to number of families |
sd.rgenspp |
standard deviation of the ratio of the number of genera to number of families |
Rick Condit, Suzanne Lao and Pamela Hall
## Not run: 1. almost default use, with fewer replicates to get a result in a shorter amount of time sgf.out <- sgf.meanarea(bci90.full,bcispp.info,replicates=10) ## End(Not run)