Figure 4
pH profiles in (a) Yingtan (YT) and (b) Qianjiang (QJ) paddy soils measured at different distances from the fertilisation site at 40 d after fertilisation. A 25-μm-diameter pH microelectrode was used (pH 25, Unisense, Aarhus, Denmark). CK, without N fertilisation. The ordinate represents the depth of the water layer (0–1,000 μm) and soil (0–9,000 μm), and the tick label of “0” shows the water-soil interface. The pH profile was determined in the right and left compartments of each box and in the center at different distances from the nylon nets in each treatment. Profile results in repeats were so similar that a representative result is shown.
