Learn R Programming

medfate (version 4.7.0)

pheno_updateLeaves: Leaf phenology

Description

Function pheno_leafDevelopmentStatus returns the expanded status (0 to 1) of leaves according to the growth degree days required to start bud burst and leaf unfolding, as dictated by a simple ecodormancy (one-phase) model (Chuine et al. 2013). Function pheno_leafSenescenceStatus returns the 0/1 senescence status of leaves according to the one-phase senescence model of Delpierre et al. (2009) on the basis of photoperiod and temperature. Function pheno_updateLeaves updates the status of expanded leaves and dead leaves of object x given the photoperiod, temperature and wind of a given day. It applies the development model for 1 < doy < 180 and the senescence model for 181 > doy > 365.

Usage

pheno_leafDevelopmentStatus(Sgdd, gdd, unfoldingDD = 300)

pheno_leafSenescenceStatus(Ssen, sen)

pheno_updatePhenology(x, doy, photoperiod, tmean)

pheno_updateLeaves(x, wind, fromGrowthModel)

Value

Function pheno_leafDevelopmentStatus returns a vector of values between 0 and 1, whereas function pheno_leafSenescenceStatus returns a vector of 0 (senescent) and 1 (expanded) values. The other two functions do not return any value (see note).

Arguments

Sgdd

Degree days required for leaf budburst (in Celsius).

gdd

Cumulative degree days (in Celsius)

unfoldingDD

Degree-days for complete leaf unfolding after budburst has occurred.

Ssen

Threshold to start leaf senescence.

sen

Cumulative senescence variable.

x

An object of class spwbInput.

doy

Day of the year.

photoperiod

Day length (in hours).

tmean

Average day temperature (in Celsius).

wind

Average day wind speed (in m/s).

fromGrowthModel

Boolean flag to indicate that routine is called from growth simulation function.

Author

Miquel De Cáceres Ainsa, CREAF

References

Chuine, I., De Cortazar-Atauri, I.G., Kramer, K., Hänninen, H., 2013. Plant development models. Phenology: An Integrative Environmental Science. Springer, pp. 275–293.

Delpierre N, Dufrêne E, Soudani K et al (2009) Modelling interannual and spatial variability of leaf senescence for three deciduous tree species in France. Agric For Meteorol 149:938–948. doi:10.1016/j.agrformet.2008.11.014

See Also

spwb, spwbInput