Assessment of the relationship between spectral indices from satellite remote sensing and winter oilseed rape yield
¹UNED Department of Mathematical and Fluid Physics, Science Faculty,
C/Senda del Rey, nº9, ES280 40 Madrid, Spain
²Czech University of Life Sciences Prague, Faculty of Engineering, Department of
Machinery Utilization, Kamýcká 129, CZ165 21 Prague, Czech Republic
³Czech University of Life Sciences in Prague, Faculty of Engineering, Department of
Agricultural Machines, Kamýcká 129, CZ165 21 Prague, Czech Republic
*Correspondence: kumhalova@seznam.cz
Abstract:
Winter oilseed rape (Brassica napus L.) belongs among the most common and strategic
crops in the Czech Republic. Growth and vitality status, yield potential and yield prediction of
oilseed rape on plots of different sizes can be effectively examined using remote sensing. That is
why the main aim of this study was to discuss a possibility of deriving spectral indices for an
assessment which spectral index is more adequate to forecast oilseed winter rape development
and consequent yield in the Czech Republic. Information about the winter oilseed rape growth
and yield was collected in three years – 2004, 2008, 2012. A relationship between grown crops
and selected vegetation indices was evaluated. The Landsat 7 satellite images were selected as a
source for deriving spectral indices. The relationship between each spectral index and yield was
analysed in 2012 only. Five images on different dates during the whole life of winter oilseed rape
were found during this year. The images from the years 2004 and 2008 were cloudier. The spectral
indices showing the best relationship with yield from 2012 were then analysed in the images from
2004 and 2008. The results showed that Enhanced Moisture Stress Index is the most acceptable
index from the selected indices used in this study. From an agronomical point of view no available
index was found to be suitable for the winter rape growth evaluation due to dependence on
precipitation conditions. For monitoring of the yield components in winter oilseed rape in
conditions of the Czech Republic, it seems necessary to develop a new vegetation index which
will reliably describe the winter oilseed rape growth stages during the whole vegetation season.
Key words:
Landsat 7 images, Remote sensing, spectral indices, winter oilseed rape, yield rating