clim.twd {dendRoAnalyst}

Calculating relative growth change during no-rain periods.

Description

This function calculates the number and the location of climatically adverse periods within a climate time series. The user can define a duration and threshold of these conditions. The function also provides the relative radial/circumferencial change during each adverse period for the original or normalized data. See Raffelsbauer et al., (2019) for more details.

Usage

clim.twd(
  df,
  Clim,
  dailyValue = "max",
  thresholdClim = "<10",
  thresholdDays = ">5",
  showPlot = TRUE
)

Arguments

df

dataframe with first column containing date and time in the format yyyy-mm-dd HH:MM:SS and the dendrometer data in following columns.

Clim

dataframe with the first column containing Date in yyyy-mm-dd and second column containing corresponding climate data.

dailyValue

either 'max', 'min', 'mean', or 'sum' for selecting the daily resampled value. Default is 'max'. See dendro.resample for details.

thresholdClim

string, the theshold for the respective climatic parameter. E.g. if climatic data is precipitation then days, where precipitation is below or equal to this value, are considered as adverse climate. Dafault is '<10'.

thresholdDays

string, the minimum number of consecutive adverse days to be considered for analysis. For example, thresholdDays=2 means the relative radial/circumferential change is calculated for adverse periods lasting for more than 2 days. Default is '>5'.

showPlot

logical, if TRUE, generates plots.

Value

A dataframe containing the respective periods, relative radial/circumference change for each tree, the ID for each period and their beginning and end.

References

Raffelsbauer V, Spannl S, Peña K, Pucha-Cofrep D, Steppe K, Bräuning A (2019) Tree Circumference Changes and Species-Specific Growth Recovery After Extreme Dry Events in a Montane Rainforest in Southern Ecuador. Front Plant Sci 10:342. doi:10.3389/fpls.2019.00342

Examples

library(dendRoAnalyst)
data(gf_nepa17)
data(ktm_rain17)
relative_dry_growth<-clim.twd(df=gf_nepa17, Clim=ktm_rain17, dailyValue='max', showPlot=TRUE)
1

head(relative_dry_growth,10)