Extended Data Fig. 5: Critical values for soil pH, total and dissolved cadmium across paddy sites.

(a) critical soil pH. (b) Critical total cadmium contents in soil (mg kg−1). (c) Critical cadmium concentration in soil solution (µg L−1). Boxplots show medians (black lines), interquartile ranges (25th–75th percentiles), and 90% ranges (5th–95th percentiles) across 56 paddy sites in Qiyang County. Red dots indicate means, diamonds denote observed means, and dots represent outliers.