On the use of dorsiventral reflectance asymmetry of hornbeam (Carpinus betulus L.) leaves in air pollution estimation.

This study examines the role of dorsiventral leaf measurements in reflectance-based air quality estimation. The dorsiventral asymmetry is used to describe the difference between the upper (adaxial) and lower (abaxial) leaf side. Spectral characteristics of dorsiventral asymmetry and both adaxial and abaxial leaf reflectance are investigated for a typical dicotyledonous species Carpinus betulus used in an urban environment. The link with traffic-related air pollution is established and the potential for monitoring of air quality is evaluated. We conclude that dorsiventral reflectance asymmetry is a factor that should not be ignored in canopy measurements and modeling. On the other hand, the benefits of dorsiventral asymmetry indices as a tool for reflectance-based air quality seem limited.