extremely significantP < 0.001
The 3-year TP had the highest content, whereas the 5-year sample showed a significant decrease ( P < 0.01) and the 15-year TP exhibited an extremely significant reduction ( P < 0.001).
The 3-year TP had the highest content, whereas the 5-year sample showed a significant decrease ( P < 0.01) and the 15-year TP exhibited an extremely significant reduction ( P < 0.001).