G. P. Keydan

Relationship between gross primary production and chlorophyll content in crops: Implications for the synoptic monitoring of vegetation productivity

CO2/m 2 s in maize (GPP ranged from 0 to 3.1 mg CO2/m 2 s) and less than 0.2 mg CO2/m 2 s in soybean (GPP ranged from 0 to 1.8 mg CO2/m 2 s). Validation using an independent data set for irrigated and rainfed maize showed robustness of the technique; RMSE of GPP prediction was less than 0.27 mg CO2/m 2 s.

Proximal Sensing of Coral Features: Spectral Characterization of Siderastrea siderea

Remote sensing has been suggested as a potential tool for monitoring coral-reef ecosystems. However, before remote sensing can be viewed as a practical monitoring and diagnostic tool for entire coral communities, there is a need to understand the spectral responses from individual coral species. Toward that end, it seems important to not only establish the range of natural variability in spectral reflectance but also to develop procedures to enhance understanding of the spectra. This paper describes our data collection approach as well as a procedure for examining the spectral features associated with one species of coral (Siderastrea siderea). The paper also examines the spectral variability in reflectance within samples of the same species and suggests a procedure for highlighting the spectral positions of absorbers/pigments, thus yielding useful information about pigment composition in one coral species.