R/avasoilmoisture.R

In rutujact/avasoilmoisture: Compiles soil moisture data from Matteo's BCI Ava Tower TDR probes.

#' avasoilmoisture: A package for soilmoisture data collected by Matteo at the AVA tower north of BCI
#'
#' Compiles data from vertical (0-15 cm) and horizontal (10, 40 and 100 cm) TDR probes collected by Matteo at the AVA tower north of BCI.
#' Derived SWC and Saturation Index derived from TDR data are presented.
#' Provides datasets in four forms:
#'
#' tdr : all probes, 5 min interval
#'
#' tdr.daily : all probes, daily means
#'
#' horizontal : 10, 40 and 100 cm probes, 5 min interval
#'
#' vertical : three 0-15 cm vertical probes; 5 min interval
#'
#' @section Details
#' Data was collected from three replicates of vertical TDRs covering 0-15 cm depths at 5 min interval at the AVA Tower beginning July 4, 2012.
#' In Jan 18, 2016 three horizontal probes were added at 10, 40 and 100 cm depth.
#'
#' By collecting gravimetric soil water content, a calibration curve was fitted by Matteo for 0-15 cm depth with the model  below:
#' tdr_model(x) = p1*x^3 + p2*x^2 + p3*x + p4
#'
#' Coefficients (with 95 percent confidence bounds):
#'
#' p1 =    0.001375  (0.0002419, 0.002508)
#'
#' p2 =     -0.1161  (-0.2152, -0.01708)
#'
#' p3 =       3.277  (0.4036, 6.151)
#'
#' p4 =      -30.57  (-58.23, -2.915)
#'
#' In this 0-15 cm top layer, soil porosity is high (bulk density as measured by Matteo for 0-15 cm layer is 0.75-0.8 g cm-3), but porosity decreases with depth and bulk density is high (1-1.3 g cm-3; see clm_fates_hydrology/data-raw/BCI 50 ha plot soil texture_Matteo_average.xls). So the above equation may not apply. So better to use Saturation Index = SWC/porosity x 100
#'
#' The package combines the TDR data for all years, converts it to SWC (m3/m3)--albeit using the same TDR_to_SWC model for all the depths. And calculates saturation index by dividing swc with max swc value by depth.
#'
#' @docType package
#' @name avasoilmoisture
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