PG: Constructor of PG weighted waveband

View source: R/pg.r

PGR Documentation

Constructor of PG weighted waveband

Description

Plant growth BSWF of Flint and Caldwell

Usage

PG(norm = 300, w.low = 275, w.high = 390)

Arguments

norm

normalization wavelength (nm)

w.low

short-end boundary wavelength (nm)

w.high

long-end boundary wavelength (nm)

Details

The mathematical formulation included by Flint and Caldwell (2003) as an appendix is used. While this formulation is consistently used, the range of wavelengths over which it has been applied has varied. We use the approach of the NSF UV network and extrapolate up to 390 nm. The widely used simulation program TUV uses, instead, 366 nm as the boundary, which makes a significant difference to the computed irradiance values in sunlight.

Value

a waveband object wavelength defining wavelength range, weighting function and normalization wavelength.

Note

In the original publication [1], the long-end wavelength boundary is not specified. The longest wavelength at which the plant response was measured is 366 nm. From the data there is no evidence that action would immediately drop to zero at longer wavelengths. We have used in earlier versions the same value as used by the 'NSF Polar Programs UV Monitoring Network' as described in https://web.archive.org/web/20220130091146/http://uv.biospherical.com/Version2/description-Version2-Database3.html.

We use 390 nm as default value for w.high, but make if possible for the user to set a different wavelength. To reproduce the output of the TUV simulation model [3] version 5.0 set w.high = 366. The effect on the RAF and doses of changing this wavelength boundary is substantial, as discussed by Micheletti et al. [2]. Consequently, the value used must be always reported to ensure reproducibility. For comparisons with previous reports one may need to recompute effective irradiances using matching wavelength boundaries on a case by case basis.

References

[1] Flint, S. and Caldwell M. M. (2003) A biological spectral weighting function for ozone depletion research with higher plants Physiologia Plantarum, 2003, 117, 137-144

[2] Micheletti, M. I.; Piacentini, R. D. & Madronich, S. (2003) Sensitivity of Biologically Active UV Radiation to Stratospheric Ozone Changes: Effects of Action Spectrum Shape and Wavelength Range Photochemistry and Photobiology, 78, 456-461

[3] https://www2.acom.ucar.edu/modeling/tropospheric-ultraviolet-and-visible-tuv-radiation-model

See Also

GEN_G GEN_T GEN_M and waveband

Other BSWF weighted wavebands: CH4(), DNA_GM(), DNA_N(), DNA_P(), FLAV(), GEN_G(), GEN_M(), GEN_T(), PAR(), UV_health_hazard(), erythema()

Examples

PG()
PG(300)


photobiologyWavebands documentation built on Oct. 24, 2023, 5:07 p.m.