Overal function for Nowacki and Abrams 1997 method.

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Description

Radial-growth averaging criteria developed by Nowacki & Abrams (1997).

Usage

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growthAveragingALL(data, releases = NULL, m1 = 10, m2 = 10, 
  buffer = 2, drawing = TRUE, criteria = 0.25, criteria2 = 0.5, 
  prefix = "ga", gfun = mean, length = 2, storedev = pdf, ...)

Arguments

data

A data.frame with series as columns and years as rows such as that produced by read.* function of dplR .

releases

Optional parameter usable for precomputed releases.

m1

Determines the number of years to be averaged (including target year) for period prior the potential releas.

m2

Determines the number of years to be averaged (including target year) for period prior the potential releas.

buffer

Number of years determining how close to one another two releases can be.

drawing

If TRUE, graphical outputs for individual trees.

criteria

Threshold for detection of moderate release

criteria2

Threshold for detection of major release.

prefix

Prefix of saved files.

gfun

Determines if M1 and M2 values are mean or median for selected period.

length

Determines how many years have to be given critera exceeded to be considered as release.

storedev

Format for saving the graphical outputs, eg. pdf or jpeg.

...

Details

Radial-growth averaging criteria developed by Nowacki & Abrams (1997) is one of the most often used techniques from this category. This method computes the percentage growth change (%GC) between average radial growth over the preceding 10-year period, M1 (including the target year), and average radial growth over the subsequent 10-year period, M2 (excluding the target year): %GC = [(M2-M1)/M1] * 100. Minimum threshold for release is 25% growth change for moderate and >50% for major release. The advantage of this method is its broad applicability even for a small number of samples, and that information about species autecology is not necessary. On the other hand, this generality of radial-growth averaging may lead to detection of false releases and missing of true releases (Black & Abrams 2003; Fraver & White 2005). These inaccuracies are primarily caused by different growth rates in young, small, and suppressed trees when compared to older, larger and dominant trees.

Value

Write many tables and figures in the current directory.

Note

Check the reference.

Author(s)

Pavel Fibich <pavel.fibich@prf.jcu.cz>, Jan Altman <altman.jan@gmail.com>, Tuomas Aakala <tuomas.aakala@helsinki.fi>, Jiri Dolezal <jiriddolezal@gmail.com>

References

Nowacki, G.J. & Abrams, M.D. 1997. Radial-growth averaging criteria for reconstructing disturbance histories from presettlement-origin oaks. Ecological Monographs, 67, 225-249.

See Also

noblabrams, doAll

Examples

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