Research Journal of Agriculture and Environmental Management. Vol. 2(12), pp. 403-411, December, 2013 Available online at http://www.apexjournal.org ISSN 2315 - 8719© 2013 Apex Journal International Full Length Research Spatial analysis of soil fertility estimates and NDVI in south-western Nigeria: A new paradigm for routine soil fertility mapping Fabiyi O.O. 1 *, Ige-Olumide O. 1 and Fabiyi A.O. 3 1 Regional Centre for Training in Aerospace Surveys, O.A.U. Campus. Ile-Ife, Nigeria. 2 Agricultural Research Council of Nigeria. Abuja, Nigeria. Accepted 8 November, 2013 Agricultural practice in Nigeria is still largely at the crude and primary extractive levels where farming is characterised by lack of empirical evidence to identify fertile soil and adopt the farming practice. This deficiency calls for a new approach for detecting soil fertility rapidly and routinely. The study derived estimates of soil fertility from the vegetation quality using the Normalized Difference Vegetation indices (NDVI) obtained from the satellite remote sensing data in the South- Western Nigeria. Landsat image data (bands 3 and 4) acquired in 2002 were used to compute the NDVI of the study areas while the soil map classification by FAO was used to derive soil fertility index based on the alluvium content of the soil capacity to free nutrient for plant use. The study showed tthere is significant relationship between spatial pattern of soil fertility and the normalised difference vegetal quality. Regression analysis shows the r 2 value is 0.75 which indicated that the chlorophyll levels of the vegetation in the south-western Nigeria can be explained by the soil fertility index. The study posited that rapid soil fertility maps can be generated from NDVI of remote sensing data and can be used to further improved agricultural production in Nigeria and other developing countries. Key words: Agricultural development, fertility map, NDVI, poverty reduction. INTRODUCTION There is growing evidence that soil fertility is on the decline in many African soils. This resulted in decline in agricultural output and further entrenching poverty in the continent. The drive towards agricultural revolution is hindered by absence or low quality databases for agricultural planning. One of the databases that is poignant for agricultural planning is soil map or soil fertility map which can help agricultural planners and decision makers know the best model of agricultural revolution to be adopted in different provinces. Today Most African countries still depend on subsistence *Corresponding author. E-mail: seyifabiyi@yahoo.com. Tel: +234-8034085463 Agriculture with little scientific input from the research communities and local technological advanced industries. Where available, soil maps are either outdated or coarse in a way that no meaningful development programme can be based in such maps. Most comprehensive soil maps at the national scale in Africa are dated and are not useful for current agricultural development programmes. There is no programme or method to rapidly and routinely update soil map without extensive and laborious field studies. This calls for a less expensive approach to estimating soil fertility and agricultural potential of soil for better performance. Soil mapping especially at the national or provincial scale have been found to be very expensive and are rarely done by government or by local framers. This calls for a cheaper and more frequent way of estimating the soil fertility so that regular agricultural