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ZeBook (version 0.3)

maize.model: The basic Maize model function

Description

Model description. This model is a dynamic model of crop growth for Maize cultivated in potential conditions. The crop growth is represented by three state variables, leaf area per unit ground area (leaf area index, LAI), total biomass (B) and cumulative thermal time since plant emergence (TT). It is based on key concepts included in most crop models, at least for the "potential production" part. In fact, this model does not take into account any effects of soil water, nutrients, pests, or diseases,... The tree state variables are dynamic variables depending on days after emergence: TT(day), B(day), and LAI(day). The model has a time step dt of one day. The model is defined by a few equations, with a total of seven parameters for the described process. (1) $TT(day + 1) = TT(day ) + dTT(day)$

Usage

maize.model(Tbase, RUE, K, alpha, LAImax, TTM, TTL,
    weather, sdate, ldate)

Arguments

Tbase,RUE,K,alpha,LAImax,TTM,TTL
: 7 parameters
weather
: weather data.frame for one single year
sdate
: sowing date
ldate
: last date

Value

  • data.frame with daily TT, LAI,B