Table 4 Evaluation standard for eutrophication of reservoirs.
From: Characterization and evaluation of Fe2+ and Mn2+ in reservoirs and sediments in the Jianghuai Region
Degree of eutrophication | Level of eutrophication | PI value |
|---|---|---|
Not eutrophic | Ⅰ | PI﹤0.2 |
Lightly enriched | Ⅱ | 0.2 ≤ PI﹤1 |
Moderately nutrient-rich mesotrophic | III | 1 ≤ PI﹤5 |
Heavy nutrient enrichment | IV | 5 ≤ PI﹤10 |
Severe eutrophication | V | PI ≥ 10 |
