Function hydrology_rainInterception calculates the amount of rainfall intercepted daily by the canopy, given a rainfall and canopy characteristics. Two canopy interception models are currently available: the sparse Gash (1995) model and the Liu (2001) model. In both cases the current implementation assumes no trunk interception.
hydrology_rainInterception(Rainfall, Cm, p, ER=0.05, method="Gash1995")
hydrology_erFactor(doy, pet, prec, Rconv = 5.6, Rsyn = 1.5)
hydrology_interceptionPlot(x, SpParams, ER = 0.05, gdd = NA, throughfall = FALSE)Function hydrology_rainInterception returns a vector of the same length as Rainfall containing intercepted rain values. Function hydrology_erFactor returns a scalar with the evaporation-to-rainfall ratio.
A numeric vector of (daily) rainfall.
Canopy water storage capacity.
Proportion of throughfall (normally 1 - c, where c is the canopy cover).
The ratio of evaporation rate to rainfall rate.
Rainfall interception method (either "Gash1995" or "Liu2001").
Day of the year.
Potential evapotranspiration for a given day (mm).
Precipitation for a given day (mm).
Rainfall rate for convective storms and synoptic storms, respectively, in mm/h.
An object of class spwbInput.
A data frame with species parameters (see SpParamsMED and SpParamsMED).
Growth degree days (in Celsius).
Boolean flag to plot relative throughfall instead of percentage of intercepted rainfall.
Miquel De Cáceres Ainsa, CREAF
Function hydrology_rainInterception can accept either vectors or scalars as parameters Cm, p and ER. If they are supplied as vectors they should be of the same length as Rainfall.
Function hydrology_erFactor calculates the evaporation-to-rainfall ratio for input values of potential evapotranspiration and rainfall, while accounting for seasonal variation in rainfall intensity (mm/h). Default values Rconv = 5.6 and Rsyn = 1.5 come from Miralles et al. (2010).
Liu (2001). Evaluation of the Liu model for predicting rainfall interception in forests world-wide. - Hydrol. Process. 15: 2341-2360.
Gash (1979). An analytical model of rainfall interception by forests. - Quarterly Journal of the Royal Meteorological Society.
Gash et al. (1995). Estimating sparse forest rainfall interception with an analytical model. - Journal of Hydrology.
Miralles DG, Gash JH, Holmes TRH, et al (2010) Global canopy interception from satellite observations. J Geophys Res 115:D16122. doi: 10.1029/2009JD013530.
spwb
#Load example plot plant data
data(exampleforestMED)
#Default species parameterization
data(SpParamsMED)
#Draw rainfall interception for two values of the E/R ratio
hydrology_interceptionPlot(exampleforestMED, SpParamsMED, ER = c(0.05, 0.2))
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