| # | Concept | Culture | Statement | Freq. |
|---|---|---|---|---|
| 1 | irrigation | Sudan | Traditional use of irrigation along the Nile River for agriculture | 1 |
| 2 | irrigation in agriculture | Sudan | Ancient and highly developed due to dependence on the Nile River for agriculture | 1 |
| 3 | irrigation system | Sudan | Traditional irrigation methods have been practiced along the Nile River for thousands of years. | 1 |
| 4 | irrigation systems | Sudan | Historically relied on Nile River for irrigation, giving rise to advanced hydraulic engineering techniques | 1 |