| growth.indiv {CTFS} | R Documentation |
Computes annual growths rate for individual trees and returns a dataframe of these values for all trees. Two types of growth rates are computed: annual dbh increment (mm dbh per year), relative growth rate (% change in dbh per year). Growth rates can also be evaluated for unrealistically high and low values and removed from the summary values. The dataset must have at least 2 censuses to compute growth.
growth.indiv(census1, census2,
rounddown = FALSE, mindbh = 10, err.limit = 4, maxgrow = 75)
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 |
rounddown |
logical value in caps. When TRUE, if either of
census is < 55, then the floor of the dbh value / 5 is
provided. When FALSE, no change in the dbh is made. |
mindbh |
minimum DBH in census1 for inclusion in computation. |
err.limit |
number of standard deviations: used for determining if an individual tree growth rate is too high or low for inclusion. |
maxgrow |
maximum absolute growth rate, mm per year: used for determining if an individual tree growth rate is too high for inclusion. |
See CTFS.growth for details on the computation methods
of growth rates and associated functions.
Any two censuses on a datafile must be used. They do not have to be
sequential, only that census1 has to be before census2.
The results of growth.indiv are growth rates for individual
trees, NOT MEAN GROWTH VALUES. A value is returned for
each tree. If growth is invalid then NA is returned.
growth.indiv returns a dataframe with the
following components:
tag |
tree individual tag number |
sp |
species code |
gx |
"x" coordinate of tree within the plot |
gy |
"y" coordinate of tree within the plot |
dbh1 |
DBH at the first census as defined by user |
dbh2 |
DBH at the second census as defined by user |
years |
interval, in years, between censuses |
incgr |
annual growth; (dbh2 - dbh1) / time |
expgr |
relative growth; (log(dbh2)-log(dbh1))/time |
Rick Condit
## Not run:
1. Default use of growth.indiv(). Warning messages may result from
computation of exponential growth. The values will be set to
NA in the returned \strong{dataframe}
growth.indiv.out <- growth.indiv(tst.bci90.full,tst.bci95.full)
2. Selecting a single species for growth.indiv()
growth.alsebl.tree < -growth.indiv.out[growth.indiv.out$sp=="alsebl",]
## End(Not run)