Assessment of MODIS imagery to track light-use efficiency in a water limited Mediterranean pine forest

Gross primary production (GPP) measurements obtained from an eddy-covariance flux 14 tower have been used to analyze the information content of MODIS Photochemical Reflectance Index (PRI) data on light-use efficiency (LUE) temporal variations. The study has been conducted in a Mediterranean Pinus pinaster forest showing summer water stress. Advanced processing techniques have been used to analyze the effect of 18 various external factors on LUE and PRI variations. Most intra-annual correlation between the two variables has been found to be attributable to concurrent variations in illumination and viewing conditions. A PRI normalized from angular effects is then introduced (NPRI), which is able to track ecosystem LUE response to prolonged summer water limitations. Some possible eco-physiological reasons are provided for this phenomenon, whose potential for real-time GPP estimation is, however, limited by an observed shift between LUE and NPRI signals.

MORENO Alvaro;  MASELLI Fabio;  GILABERT Maria Amparo;  CHIESI M.;  MARTINEZ Beatriz;  SEUFERT Guenther; 

2012-06-11

ELSEVIER SCIENCE INC

JRC70017

0034-4257,   

http://www.sciencedirect.com/science/article/pii/S0034425712001642,    https://publications.jrc.ec.europa.eu/repository/handle/JRC70017,   

10.1016/j.rse.2012.04.003,