Photosynthetically relevant solar radiation that reaches the surface of Earth is divided into three main spectral regions: ultraviolet-B (UV-B) (290 to 315 nm), UV-A (315 to 400 nm), and photosynthetically active radiation (PAR) (400 to 700 nm). Among those, the UV-B region is selectively attenuated by the stratospheric ozone layer [1,2]. In contrast, the UV-A and PAR radiations have no selective absorber and are affected mainly by light scattering. The biologically most damaging wavelengths below 290 nm, such as the UV-C (200 to 290 nm) region, are absorbed almost completely by the atmosphere and are therefore unimportant for biological processes under natural conditions. Thus, depletion of stratospheric ozone, which occurs as a consequence of human activities, specifically enhances the UV-B radiation reaching the Earth [3-7].
ASJC Scopus subject areas
- Agricultural and Biological Sciences(all)