Research Article
Evaluation Models for Soil Nutrient Based on Support Vector Machine and Artificial Neural Networks
Table 1
The evaluation criterion of soil nutrient content.
| Rank | Organic matter/g·kg−1 | Total nitrogen/g·kg−1 | Alkali-hydrolysable nitrogen/mg·kg−1 | Rapidly available phosphorus/mg·kg−1 | Rapidly available potassium/mg·kg−1 |
| 1 | >40 | >2.0 | >150 | >40 | >200 | 2 | 30–40 | 30–40 | 120–150 | 20–40 | 150–200 | 3 | 20–30 | 20–30 | 90–120 | 10–20 | 100–150 | 4 | 10–20 | 10–20 | 60–90 | 5–10 | 50–100 | 5 | 6–10 | 6–10 | 30–60 | 3–5 | 30–50 | 6 | <6 | <0.5 | <30 | <3 | <30 |
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