grlyr: Ground Layer Estimation

#' grlyr: A package for ground layer estimation.
#'
#' Estimates biomass, carbon and nitrogen of moss and lichen ground
#'      layers as part of the US Forest Service Forest Inventory and
#'      Analysis program.
#'
#' @section Datasets:
#'
#'      \code{\link{cal}} is calibration data from destructive
#'      sampling.
#'      \code{\link{est}} is estimation data from nondestructive
#'      sampling at sites where estimates are desired.
#'
#' @section Functions:
#'
#'      \code{\link{check_dat}} checks that estimation data are in
#'      proper format.\cr
#'      \code{\link{calc_biomass}} is the core function to calculate
#'      ground layer metrics (prominently including biomass).\cr
#'      \code{\link{summary_plot}} produces summaries at the
#'      plot-level, the expected level of summarization for USFS-FIA.
#'      \cr
#'      \code{\link{summary_fg}} produces summaries at the level of
#'      functional groups.\cr
#'      \code{\link{plot_map}} plots a map of geographic locations
#'      colored by some value.\cr
#'      \code{\link{plot_facet}} plots a scatterplot or histogram of
#'      values faceted by some grouping variable (such as functional
#'      groups).
#'
#' @section Bibliography:
#'
#'      FIA [Forest Inventory and Analysis Program]. 2018. Field
#'      Instructions for the Annual Inventory of Alaska 2018:
#'      Supplement for Interior Alaska. USDA Forest Service, Pacific
#'      Northwest Research Station, Anchorage, Alaska.
#'
#'      Pattison, R., H.-E. Andersen, A. Gray, B. Schulz, R. J. Smith,
#'      and S. Jovan. 2018. Forests of the Tanana Valley State Forest
#'      and Tetlin National Wildlife Refuge, Alaska: results of the
#'      2014 pilot inventory. Page 80. Gen. Tech. Rep. PNW-GTR-967, US
#'      Department of Agriculture, Forest Service, Pacific Northwest
#'      Research Station, Portland, OR.
#'
#'      Smith, R. J., J. C. Benavides, S. Jovan, M. Amacher, and B.
#'      McCune. 2015. A rapid method for landscape assessment of
#'      carbon storage and ecosystem function in moss and lichen
#'      ground layers. The Bryologist 118:32–45.
#'
#'      Smith, R. J., S. Jovan, A. N. Gray, and B. McCune. 2017.
#'      Sensitivity of carbon stores in boreal forest moss mats -
#'      effects of vegetation, topography and climate. Plant and Soil
#'      421:31–42.
#'
#'      Smith, R. J., S. Jovan, and B. McCune. 2014. Ubiquitous moss
#'      and lichen mats promote forest health. Pages 68–69 in E.
#'      Graham and T. Huette, editors. Forest Health Conditions in
#'      Alaska 2013. R10-PR-035. USDA Forest Service, Alaska Region,
#'      Anchorage, Alaska.
#'
#' @docType package
#' @name grlyr
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