Figure 6. Soil δ¹⁵N content and total soil N content at the beginning vs the end of the mesocosm experiments.

(a) δ¹⁵N value in soil at the beginning and end of the mesocosm experiments. (b) Total N in soil at the beginning and end of the mesocosm experiments. Values are means ± SE (n = 6). An asterisk indicates a significant difference between the before and after values for each treatment in each rice-aquatic system at p < 0.05; ns indicates that the difference was not statistically significant.