Using Geographic Information Systems to assess the distribution of major soil nutrient contents in the Northern Region of Ghana

Abstract

Some soil factors influence the spatial distribution of soil nutrients at different locations. The study therefore assesses the association between Nitrogen (N), Phosphorus (P) and Potassium (K) concentration levels at 16 districts of the Northern Region of Ghana and factors such as average quantity of fertilizer application, soil pH and topographical elevation of the districts using spatial regression models in Geographic Information Systems. Results of the study indicated that association between amount of fertilizer used by farmers and soil N, P and K contents were negative (coefficient values: N (%) = -0.0003; P (mg kg-1) = -0.0023; and K (cmolc kg-1) = -0.001); an indication that high amount of fertilizer input does not necessarily contribute to high N, P and K contents in the soil and vice versa. Only the association between exchangeable K contents and average amount of fertilizer application was significant (p = 0.01). Soil pH had a positive (coefficient value of 0.1973) significant (p < 0.001) association with N contents only; whilst the terrain topography did not have any significant (p > 0.05) association with the N, P and K contents. The study recommends that fertilizer application be appropriately managed to contribute to soil nutrient fertility in the Northern Region of Ghana.