Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
4464824 | International Journal of Applied Earth Observation and Geoinformation | 2013 | 8 Pages |
•Leaf nitrogen and chlorophyll content were retrieved accurately from leaf reflectance spectra.•Canopy nitrogen and chlorophyll content were closely related.•Vegetation indices using green and red-edge spectral bands were used for accurate chlorophyll and nitrogen estimation at canopy level.•Optimal spectral bands found for nitrogen and chlorophyll estimation match well-spectral bands of near future space systems.
Leaf and canopy nitrogen (N) status relates strongly to leaf and canopy chlorophyll (Chl) content. Remote sensing is a tool that has the potential to assess N content at leaf, plant, field, regional and global scales. In this study, remote sensing techniques were applied to estimate N and Chl contents of irrigated maize (Zea mays L.) fertilized at five N rates. Leaf N and Chl contents were determined using the red-edge chlorophyll index with R2 of 0.74 and 0.94, respectively. Results showed that at the canopy level, Chl and N contents can be accurately retrieved using green and red-edge Chl indices using near infrared (780–800 nm) and either green (540–560 nm) or red-edge (730–750 nm) spectral bands. Spectral bands that were found optimal for Chl and N estimations coincide well with the red-edge band of the MSI sensor onboard the near future Sentinel-2 satellite. The coefficient of determination for the relationships between the red-edge chlorophyll index, simulated in Sentinel-2 bands, and Chl and N content was 0.90 and 0.87, respectively.