 |
| |||
| soil conservation; conservation of soil | |||
| soil protection | |||
| ground conservation | |||
| soil preservation | |||
| |||
| soil conservation; soil protection | |||
| охрана почв: 31 a las frases, 10 temas |
| Agroquímica | 1 |
| Construcción | 3 |
| Ecología | 15 |
| Economía | 1 |
| General | 4 |
| Industria energetica | 1 |
| Makárov | 3 |
| Recursos naturales y conservación de la vida silvestre. | 1 |
| Silvicultura | 1 |
| Suministro de agua | 1 |