Figure 1. Differential reflectance lidar- system.

Vegetation remote- sensing: a new field for lidar applicationsGiovanna Cecchi, Luca Pantani, Ivan PippiIstituto di Ricerca sulle Onde Elettromagnetiche del Consiglio Nazionale delle RicercheVia Panciatichi 64, I 50127 FIRENZE (Italy)Renato MagliDipartimento di Energetica dell'Universita di FirenzeVia S.Marta 3, I 50139 FIRENZE (Italy)Piero MazzinghiIstituto di Elettronica Quantistica del Consiglio Nazionale delle RicercheVia Panciatichi 56/30, I 50127 FIRENZE (Italy)AbstractVegetation remote -sensing is a quite new field for lidar investigations and only fewresults were shown in litterature. The potential of differential -reflectance and fluorescen-ce lidars in the detection of some plant -characteristics was analyzed with a particularattention to water -stress, senescence and diseas. Both systems showed a good potential invegetation remote -sensing: differential -reflectance lidars seem particularly interesting forsenescence and disease monitoring, while fluorescence lidars seem particularly suitable forwater -stress monitoring.IntroductionThe lidar (optical radar) was taken into account in the past only for atmosferic investi-gations1; a wide potential was shown in this field and some applications, like stratospheric-aerosol sounding, have now reached a quasi- routine level. Problems of weight, power supply,and fragility of lidar systems have reduced for a long time the attention on applications,like sea and land remote -sensing, where an airborne lidar is required. A second delay reasonwas the complexity of physical, chemical, and biological effects involved in laser remote -sensing of sea and vegetation.A quite large development of researches on laser remote -sensing of the sea became evidentin the last decade with applications ranging from bathymetry to phytoplancton mapping234.Only in more recent years lidar monitoring of vegetation was taken into account with aparticular emphasis on fluorescence -lidar applications567. At our institutes the researcheson lidar potential in vegetation remote -sensing begun approximately in 1982 both on differe-ntial- reflectance89 and fluorescence lidars1011. The investigations concerned the possibilityof a lidar detection of plant characteristic like senescence, water -stress, and some disea-