meaninterval.quad {CTFS}R Documentation

Mean Interval Between Census for Quadrates

Description

Computes the mean time between censuses (in years) for any user specified size quadrate (area) of plot. The user can also specify any portion of the plot (or all of it) be considered. The default quadrate size is 1 hectare.

Usage

meaninterval.quad(census1, census2, mindbh = 10, 
        plotdim = c(1000, 500), gridsize = 100,  
        xrange = c(0, plotdim[1]), yrange = c(0, plotdim[2]), 
        whichcensus = "both")

Arguments

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
mindbh Minimum DBH for computing population size in each census
plotdim dimensions of the plot: east-west 1000m and north-south 500m
gridsize side of the square quadrate, 100 x 100m (1 ha) by default
xrange the x axis of the plot used for computation, standard plot has 0-1000
yrange the y axis of the plot used for computation, standard plot has 0-500
whichcensus variable to indicate which census(es) are to be used. Values are “first”, “second”, “both”

Details

This is a generic function for any computation of dynamics. Any tree with a recorded date of when a census was done is used in this computation. This function is NOT used for the computation of mean time between censuses for the dynamic functions.

A tree is included in the computation depending upon the value of whichcensus. It must have a dbh which equals or exceed mindbh for the census specified. For “both” a tree is included if its dbh exceeds mindbh for EITHER census.

Value

meaninterval.quad returns a matrix of the mean interval, in years, for species by user defined quadrate.

$meantime mean time between intervals for all trees in quadrate

Author(s)

Rick Condit and Pamela Hall

Examples

## Not run: 
1. Default use of meaninterval.quad
meantime.both.out <- meaninterval.quad(tst.bci90.full, tst.bci95.full)
## End(Not run)

[Package CTFS version 1.00 Index]