abundance.change.dbh {CTFS} | R Documentation |
Computes annual change in population size by DBH classes. DBH class is
determined independently for each census. Any two census datasets can be
provided in order of date of census. The rate of change is computed,
but no probability is provided. For categories that do not include DBH
use abundance.change
.
abundance.change.dbh(census1, census2, alivecode = c("A"), dbhclass = c(10, 100, 300), split = NULL)
census1 |
name of census datafile for first census, must be a
dataframe, must be of same length as census2 |
census2 |
name of census datafile for second census, must be a
dataframe, must be of same length as census1 |
alivecode |
character, codes of the variable status
that indicate the tree is alive. The most general valid categories are: "A" and
"AB" and "AS". |
dbhclass |
a vector of dbh class levels - also sets minimum dbh |
split |
a vector of categorical values of the same
length as census which groups trees into classes of
interest for which abundance values are computed. This vector can be
composed of characters or numbers. |
See CTFS.abundance
for details on the computation of
abundance and associated functions.
Two censuses must be used. They do not have to be sequential, only that
census1
has to be before census2
.
The vector split
must be of the same length as census1
and
census2
but can contain NA
. The vector dbhclass
only has to contain the minimum dbh for each class of interest. A
maximum dbh does not have to be specified. The smallest value of
dbhclass is used as mindbh
.
The inclusion of a tree is determined independently for each census. The
user can only define status
and dbhclass
once. These values
are used for assessing a tree for inclusion for each census.
abundance.change.dbh
returns a list of arrays with the values
of split1
as the first dimension and the values of
split2
as the second dimension of the array. The array
contains the following named components:
$N0 |
abundance in first census |
$N1 |
abundance in second census |
$rate |
annual rate of change in abundance |
$meanyrs |
mean number of years between census for trees used in mortality rate computation |
$date0 |
mean date of first census |
$date1 |
mean date of second census |
Rick Condit, Suzanne Lao, Pamela Hall
## Not run: # 1. Default use of abundance.change.dbh abund.ch.dbh.out <- abundance.change.dbh(tst.bci90.full,tst.bci95.full) # 2. Set different dbhclasses and also by species abund.ch.dbh.sp.out <- abundance.change.dbh(tst.bci90.full,tst.bci95.full, + dbhclass=c(10,20,30,100,300),split=tst.bci90.full$sp) ## End(Not run)