Use of Multispectral Radiometer and Modis Satellite Data Correlations in Developing Models for Tobacco Yield Estimation

The multispectral radiometer (MSR5) and MODIS satellite data correlations were used in developing models for flue-cured tobacco yield estimation. A field experiment was set and a field survey and satellite Earth observations were carried out. Radiometric measurements from the experiment were used to relate normalized vegetation index (NDVI) from the multispectral radiometer to tobacco yield. Ground based MSR5 and MODIS satellite based data correlations were developed using radiometric and satellite spectral measurements collected from a 100 ha tobacco field. NDVI’s were also extracted from the freely downloaded images from 38 randomly selected tobacco fields of at least five hectares in area in the tobacco growing regions of Zimbabwe. The MSR5 based yield-NDVI correlations for the September to October planted tobacco ranged between 0.78 and 0.81, while those for the December planted and r the pooled data were 0.91 and 0.51 respectively. The upscaling factor for NDVIMSR5 from the NDVIMODIS was developed, and this, in turn was used to develop the final tobacco yield estimation model. The predicted average flue cured tobacco yield (2.72 tons/ ha) was 88% of the actual yield (3.08 t/ ha) from the project area, and a performed t-test for comparison of means showed that the two were statistically similar (p > 0.05). It is recommended that the model undergoes further test and recalibration before the tobacco sector fully relies on it for crop yield estimation.