The normalised difference vegetation index obtained from agrometeorological standard radiation sensors: a comparison with ground-based multiband spectroradiometer measurements during the phenological development of an oat canopy

Following the methodology of K. F. Huemmrich and colleagues Huemmrich et al. (1999) J Geophys Res 104:27,935–27,944], agrometeorological standard radiation sensors, i.e. two photosynthetically active radiation sensors and an albedometer, were used to measure the broadband visible and optical–infrared reflectance of an oat plot during its whole growth period. From these reflectance data – recorded as 15-min averages and pooled to daily means – the seasonal cycle of the normalised difference vegetation index (NDVI) was calculated. In addition, a ground-based multi-channel spectroradiometer was used as a reference to estimate narrowband “green” and “red” NDVIs at weekly intervals near noon. The narrowband “green” NDVI was shown to be consistent with the simultaneous broadband 15-min NDVI. This shows that the configuration of agrometeorological radiation sensors is suitable to adequately track phenological crop dynamics.

Martin KraftEmail: