Table 2 Standard values of soil environmental quality/(mg/kg).
From: Assessment of environmental impacts of heavy metal pollution in rice in Nanning, China
Project | Level 1 | Level 2 | Level 3 | |||
|---|---|---|---|---|---|---|
pH < 6.5 | 6.5 ≤ pH ≤ 7.5 | pH > 7.5 | pH > 6.5 | |||
Lead | 35 | 250 | 300 | 350 | 500 | |
Cadmium | 0.20 | 0.30 | 0.30 | 0.60 | 1.0 | |
Mercury | 0.15 | 0.30 | 0.50 | 1.0 | 1.5 | |
Arsenic | Paddy field | 15 | 30 | 25 | 20 | 30 |
The dry land | 15 | 40 | 30 | 25 | 40 | |
