Figure 7

Relative frequencies [% of all soil voxels in the respective layer] of soil-root distances at 16 DAP for representative samples given in Fig. 6, separated in 3 layers, representing the fertiliser layer (middle) and both parts above (left) and below (right) the fertiliser layer. The control treatment (“C”) is given in red, urea (“U”) in blue and urea with nitrification inhibitor (“U+NI”) in green.