Land Suitability of the Nkrankwanta Lowland for Rice Cultivation in the Dormaa West District, Ghana

Abstract

Aims: Suitability of land for growing crops, which considers the spatial distribution of soil characteristics, is an important factor to consider in order to maximize yields and ensure judicious land-use planning. This study was conducted to assess the suitability of Nzema series according to Land Suitability Classification for rainfed rice cultivation. The study was undertaken at Nkrankwanta lowland in the Dormaa West District, Ghana. Methods: Two pedons were dug at a depth of 0-140 cm for both sampling locations. A total of 50 soil samples were collected at a depth of 0-20, 20-40, 40-60, 60-100, and 100-140 cm depth. Suitability assessment was done using the FAO Land Quality Index with input parameters including pH, texture, stoniness, nitrogen, depth, organic carbon, slope, and drainage. Results: Chemical analysis revealed that nitrogen, phosphorus and organic matter were generally low. The results showed that pH for both pedons ranged from very strongly acidic to slightly alkaline (4–7.8) which could be as a result of leaching of basic cations due to the regular flooding of the lowland. The two pedons are deep >140 m and the drainage is imperfect to poorly drained. Soil Quality Index was 0.8 whilst Nutrient Availability Index was 0.05, indicating highly suitable and marginally suitable land for rice production respectively. Conclusion: Based on this analysis, Nkrankwanta lowland is marginally suitable (0.04) for rice production. The soil is potentially highly suitable if continuous monitoring of the pH status is carried out. Nutrient management is recommended to improve the low fertility status of the soil.