Fig. 6
![Fig. 6](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs12302-022-00632-0/MediaObjects/12302_2022_632_Fig6_HTML.png)
Correlation of nitrate content (median) and share of cropland in the catchment areas of 50 springs for three monitoring periods (circles/solid line = 2018, ×/dotted line = 2011–20112, +/dashed line = 2002)
Correlation of nitrate content (median) and share of cropland in the catchment areas of 50 springs for three monitoring periods (circles/solid line = 2018, ×/dotted line = 2011–20112, +/dashed line = 2002)