an increasing trendp < 0.05
Sodium (Na) shows an increasing trend across the site classification gradient, with concentrations rising from 497 ± 38 mg/kg in non-polluted sites to 721 ± 85 mg/kg in polluted areas ( p < 0.05).
Sodium (Na) shows an increasing trend across the site classification gradient, with concentrations rising from 497 ± 38 mg/kg in non-polluted sites to 721 ± 85 mg/kg in polluted areas ( p < 0.05).
All three elements show statistically significant differences among site categories ( p < 0.05), indicating a decreasing trend across site categories arranged along the pollution gradient.