The earth environment is affected by changing vegetation biomass so, it is necessary to develop an algorithm based on the physical parameter of vegetation over a wide area by using satellite data with intermediate spatial resolution (1km2) . Our goals in this study are as follows.
1. To construct a biomass estimation model using the relationship between vegetation index (VI), vegetation cover ratio (VCR), and the biomass obtained by field data.
2. To apply the field data to satellite data.
3. To evaluate the estimated biomass derived from satellite data by using meteorological station data in Mongolia.
Field measurement data obtained from 1995 to 1998 and NOAA-14 AVHRR LAC data are used. Field measurements are conducted by mobile measurement and biomass measurement (clipping grass) over a wide area. Reflectance, vegetation cover ratio, and weight of dry biomass are measured. The methodology has already succeeded in developing a method for constructing a satellite vegetation index and biomass model, that has vegetation cover as a parameter. Satellite data are processed with highly accurate geometric correction, atmospheric correction using 6S code, and composite. Biomass maps are then generated by satellite data, and field measurement data are validated using biomass data from 15 Mongolian meteorological stations.
As a result, we can estimate vegetation biomass without influence of cloud contamination and vegetation growth for a composite of NOAA AVHRR LAC data exceeding five days. The error of estimated biomass in the Ulaanbaatar-Mandalgovi area is less than 10%.
