Simple Ecosystem Model

SEM(X, params, timestep, inputs, pest = c(0, 0, 0, 1, 0), p = 1800)

Arguments

X	an array consisting of the leaf,wood,root,storage,som,SoilWater,stem density TODO need to figure out if these are the initial condition values and may be rename the array from X to something more informative.
params	a named array of SEM parameter values.
timestep	is in seconds, defaults to 30 min
inputs	a data frame with the following columns: time the day of the year PAR incoming photosynthetically active radiation, umol/m2/s temp air temperature, degrees C VPD vapor pressure deficit, kPa precip precipitation, mm
pest	phloem, xylem, leaf, root, stem a vector of pest impacts, each entry in the vector represents the percent change in the phloem, xylem, leaf, root, and stem based on the type of disruption.
p	default value of 1800, TODO figure out what this parameter does

documentation needed

Michael C, Dietze dietze@bu.edu