In the EU, aquaculture ponds cover an area of 360,000 ha and are a crucial part of
the rural landscape. As many ecosystem services (e.g., habitats for protected wildlife,
nutrient cycling, etc.) are correlated with the proportion of reed beds relative to
open-water areas, it is important in environmental studies to be able to accurately
estimate the extent and the temporal dynamics of reed cover. Here, we propose a method
for mapping reed cover in fish ponds from freely available Sentinel-2 imagery using
the normalized difference vegetation index (NDVI), which we applied to Hungary, the
third largest carp producer in the EU. The dynamics of reed cover in Hungarian fish
ponds mapped using satellite imagery show a high degree of agreement with the ground-truth
points, and when compared with data reported in the annual aquaculture reports for
Hungary, it was found that the calculation of reed cover based on the NDVI-based approach
was more consistent than the estimates provided in the report. We discuss possible
applications of this remote sensing technique in estimating reed-like vegetation cover
in fish ponds and the possible use of the results for climate change studies and ecosystem
services assessment.
