Reflectance characteristics of canopy and salinity parameters of soil were studied to investigate the relationship of reflectance of above-vegetation and salinity information of soil.The results showed that the maximum of canopy NDVI value presented at booting of rice.Throughout the whole growth stages

the canopy NDVI increased with the decrease of the whole salt

EC of surface soil

especially at booting stage.The NDVI of rice canopy was inversely related to soil Na++K+ at jointing

booting and filling stages

except for the regreening stage.The NDVI of rice canopy did not presented significant differences with the increase of soil HCO3-

Cl-

SO24-

Ca2+ and Mg>2+ at the whole stages.Therefore

the total salt

EC and Na++K+ of alkali-saline soil could be accurately predicted through measuring the canopy reflectance of rice from tillering to filling stage.