PhenoGu {phenofit} | R Documentation |
Phenology extraction in GU method (GU)
Description
Phenology extraction in GU method (GU)
Usage
PhenoGu(x, t, ...)
## S3 method for class 'fFIT'
PhenoGu(x, t = NULL, analytical = FALSE, smoothed.spline = FALSE, ...)
## Default S3 method:
PhenoGu(x, t, der1, IsPlot = TRUE, ...)
Arguments
x |
numeric vector, or |
t |
|
... |
other parameters to |
analytical |
If true, |
smoothed.spline |
Whether apply |
der1 |
the first order difference |
IsPlot |
whether to plot? |
Value
A numeric vector, with the elements of:
-
UD
: upturn date -
SD
: stabilisation date -
DD
: downturn date -
RD
: recession date
References
Gu, L., Post, W. M., Baldocchi, D. D., Black, T. A., Suyker, A. E., Verma, S. B., … Wofsy, S. C. (2009). Characterizing the Seasonal Dynamics of Plant Community Photosynthesis Across a Range of Vegetation Types. In A. Noormets (Ed.), Phenology of Ecosystem Processes: Applications in Global Change Research (pp. 35–58). New York, NY: Springer New York. doi:10.1007/978-1-4419-0026-5_2
Filippa, G., Cremonese, E., Migliavacca, M., Galvagno, M., Forkel, M., Wingate, L., … Richardson, A. D. (2016). Phenopix: A R package for image-based vegetation phenology. Agricultural and Forest Meteorology, 220, 141–150. doi:10.1016/j.agrformet.2016.01.006
Examples
# `doubleLog.Beck` simulate vegetation time-series
t <- seq(1, 365, 8)
tout <- seq(1, 365, 1)
par = c( mn = 0.1 , mx = 0.7 , sos = 50 , rsp = 0.1 , eos = 250, rau = 0.1)
y <- doubleLog.Beck(par, t)
methods <- c("AG", "Beck", "Elmore", "Gu", "Zhang") # "Klos" too slow
fit <- curvefit(y, t, tout, methods)
x <- fit$model$AG # one model
par(mfrow = c(2, 2))
PhenoTrs(x)
PhenoDeriv(x)
PhenoGu(x)
PhenoKl(x)