Abstract: In this research,the PAR (photosynthetically Active Radiation) of rice canopies (incident PAR,reflective PAR of the canopy,the transmitted PAR and the reflective PAR of water surface) of different colonies was observed. On the basis of the observation results,the reflectance of canopy,the reflectance of water surface,the absorbed photosynthetically active radiation (APAR) and the fraction of photosynthetically active Radiation (FAPAR) were calculated and the variation regularities of them were studied. The results showed that,the FAPAR of rice canopy and LAI had extremely strong correlations,with an accuracy of the correlation equation up to 88.48%. This result could be applied to linking the ground data and remote data in large-scale global change research.

Key words: Rice, Rice, Canopy, PAR (photosynthetically Active Radiation), FAPAR, LAI