Diffuse solar radiation and canopy photosynthesis in a changing environment

The sunlight received by plants is affected cloudiness and pollution. Future changes in cloud cover will differ among regions, while aerosol concentrations are expected to continue increasing globally as a result of wildfires, fossil fuel combustion, industrial Clouds aerosols increase the diffuse fraction modify spectral composition incident solar radiation, both affect photosynthesis terrestrial ecosystem productivity. Thus, an assessment how canopy leaf-level processes respond these needed part accurately forecasting future global carbon assimilation. To review their implications: first, we discuss physical basis effect clouds on radiation it penetrates atmosphere; second, consider direct absorbed transmitted plant canopies leaves; finally, assess consequences for at levels. Photobiology be atmospheric level shift toward shorter or longer wavelengths under aerosols, respectively, due different scattering. Changes microclimate enhanced also depend acclimation architectural physiological traits, such leaf area index, orientation, clumping. Together with enhancement light-use efficiency, this makes multilayered phenomenon, requiring experimental testing capture those complex interactions that determine whether produces persistent assimilation land-surface models currently predict.