D. Hamar et al., YIELD ESTIMATION FOR CORN AND WHEAT IN THE HUNGARIAN GREAT PLAIN USING LANDSAT MSS DATA, International journal of remote sensing, 17(9), 1996, pp. 1689-1699
Models for the forecasting of crop yields using remotely-sensed satell
ite data are studied intensively worldwide. After reviewing the experi
ence gained by other researchers in this held, we selected procedures
which might be suitable for the estimation of corn and wheat yields in
Hungary. In order to study the relations between various remotely-sen
sed spectral data (and their combinations) and the actually measured f
inal yields we investigated archived agricultural and Landsat MSS spec
tral data for 1984. A linear relation has been sought and found betwee
n the yield data for 47 corn and 55 wheat fields in Hajdu-Bihar county
and various weighted and summed spectral quantities. Among the vegeta
tion indices derived from satellite data and corrected for atmospheric
effects the most promising were the spectral indices sensitive to the
green biomass. The latter, summed over a certain period in the growin
g season, exhibited a regression of 45-86 per cent, depending on the c
rop and the period of summation. Using the best models we performed re
gional yield estimation studies on 295 winter wheat and 218 corn field
s. Taking half the crop fields used in the study we determined the yie
ld estimation model and used this to estimate the overall crop product
ion for the other half of the fields. The error of overall corn produc
tion estimated by this way turn out to be less than 2 per cent. The mo
del developed for winter wheat proved to be sensitive to the wheat var
iety.