Table 1 The \({I}_{geo}\) classes in relation to soil quality.

From: Pollution characteristics and ecological risk assessment of heavy metals in paddy fields of Fujian province, China

\({I}_{geo}\) classes

Soil quality

< 0

Practically uncontaminated

0–1

Uncontaminated to moderately contaminated

1–2

Moderately contaminated

2–3

Moderately to heavily contaminated

3–4

Heavily contaminated

4–5

Heavily to extremely contaminated

> 5

Extremely contaminated