Use of Landsat images for yield evaluation within a small plot

Abstract

Many factors can influence crop yield. One of the most important factors is topography, which can play a crucial role especially in dry years. Plant variability can be monitored by many methods. This paper evaluates the suitability of vegetation indices derived from satellite Landsat 5 TM data in comparison with yield, curvature and topography wetness index over a relatively small field (11.5 ha). Imageries were chosen from the years 2006 and 2010, when oat was grown and from 2005 and 2011, when winter wheat was grown. These images were taken in June in the same growth stage for every crop. It was confirmed that derived indices from Landsat images can be used for comparison with yield and selected topographic attributes and it can explain yield variability, which can be influenced by water distribution during growth stages. Correlation coefficient between moisture stress index and winter wheat yield was -0.816 in the image acquisition date of 4. 6. 2011.

Comparison of selected vegetation indices and determination of suitability for yield description on agricultural field

“…Above that, TWI is also associated with the water supply. As stated by [3], convex parts of plot tend to lose water, while the concave parts accumulate water with nutrients. Table 7 gives the results of TWI and yield relation.…”

“…Nevertheless, the crop yield variability is influenced by many factors and therefore it tends to differ year by year. The most influencing factors are topography and the weather conditions [3]. Considering the results regarding the precipitation and average temperature in particular growth stages is therefore indispensable.…”

“…Nevertheless, there is the same value of correlation coefficient (r = 0.530) indicated by oat in both seasons. Unlike wheat, oat is a crop with a shallow root system, so it is more dependent on immediate precipitation [3]. Summary statistics of the selected indices is presented by Table 2 for wheat and Table 3 for oat.…”

“…That causes a loss of certain percentage of an original dataset. As [3] state, there are still a number of advantages of LANDSAT image utilization. Besides, it is a free source of satellite data, it provides different bands of electromagnetic spectrum for VI calculation.…”

The Possibility of Using Digital Images in Assessment of Plant Canopy Development and Weed Spread

“…Satellite and aerial images are suitable methods to be used for monitoring of fields of more than a few hectares (Kumhálová et al, 2014), but their use on a plot scale is very limited. For plots of few m 2 , as well as for pot studies (Tackenberg, 2007), digital images are a cheap and easy method to use with higher resolution.…”