Long-Term Impacts of Continuous Cultivation on Soil Properties at The Institute for Agricultural Research Farm, Samaru, Nigeria

Year 2025, Volume: 9 Issue: 2, 224 - 233, 31.12.2025

Aliyu Jamila Grace Lamba Luka Ibrahim Usman Ibrahim Abdulwahab Jimoh Usman Nasir Ibrahim

Abstract

This study investigates the effects of decades of continuous cultivation on soil properties at the Institute for Agricultural Research Farm in Samaru, Nigeria. Spanning over 50 years of intensive farming, the study utilizes legacy data from a 1984 soil survey and compares it with present-day findings to evaluate changes in soil properties. Fieldwork covered nine soil units across 338.50 hectares, involving site identification and soil sampling. Results reveal significant changes in soil properties over time. Soil texture exhibited increased silt content in soil units P3 (T = 1.99, P = 0.097, MD = -90.00 g kg⁻¹), and P6 (T = 1.43, P = 0.263, MD = 88.00 g kg⁻¹) due to tillage-induced pulverization, while sand content varied (soil units: P1 (T = 0.13, P = 0.904, mean difference (MD = 60.00 g kg⁻¹) and P5 (T = -2.97, P = 0.031, MD = -28.33 g kg⁻¹) depending on erosion and deposition patterns. Soil chemical properties demonstrated notable increases in pH (P2 (T = -6.94, P = 0.001, MD = -1.39), and A2 (T = -12.97, P = 0.0001, MD = -2.21), linked to accumulation of exchangeable bases, particularly in poorly drained units. Organic carbon (P2 (T = 2.21, P = 0.075, MD = 4.11 g kg⁻¹) and P6 (T = 1.05, P = 0.338, MD = 4.55 g kg⁻¹)) and total nitrogen levels showed declines in some soil units due to continuous cropping of non-leguminous crops and increased mineralization, while other units benefited from legume cultivation. Cation exchange capacity and base saturation decreased across most units, reflecting nutrient depletion and reduced organic matter inputs. The findings emphasize the detrimental effects of continuous cultivation on soil fertility. To mitigate these effects and improve soil health, the study recommends adopting sustainable practices such as organic and inorganic fertilizer application, conservation tillage, and proper residue management. These interventions are critical to restoring soil productivity and ensuring agricultural sustainability in the region.

Keywords

Soil Degradation , Soil Fertility , Nutrient Depletion , Agricultural Sustainability

References

• Abaje I. B., Ishaya S. & Usman, S. U. 2010. An Analysis of Rainfall Trends in Kafanchan, Kaduna State, Nigeria. Research Journal of Environmental and Earth Sciences, 2(2), 89-96. Aina P.O. 1979. Soil changes resulting from long-term management practices in Western Nigeria. Soil Science Society of America Journal. 43, 173-177.
• Aweto A.O. & Ayuba H.K. 1993. Effect of Continuous Cultivation with Animal Manuring on a Sub-Sahelian Soil near Maiduguri, Northeastern Nigeria. Biological Agriculture & Horticulture, 9(4), 343-352.
• Bezabih B., Aticho A., Mossisa T. & Dume B. 2016. The effect of land management practices on soil physical and chemical properties in Gojeb Sub- River Basin of Dedo District, Southwest Ethiopia. Journal of Soil Science and Environmental Management. 7(10), 154- 165
• Blake G.R. & Hartge K.H. 1986. Soil bulk density and particle density determination. In: Klute, A. (ed.). Methods of Soil Analysis, American Society of Agronomy, Madison, Wisconsin USA.
• Bremner J.M.& Mulvaney C.S. 1982. Nitrogen - Total. p. 595-624. In A.L. Page,
• Ernest C.I & Mbah C.N. 2016. Impact of Continuous Cultivation on Soil Properties of Imo State Southeastern Nigeria. Agrochemistry and Soil Science. 85:47-53
• Gee G.W. & Or D. 2002. Particle size analysis. In: J.H. Dane and G.C. Topp (eds).
• Methods of soil analysis, part 4. physical methods. Soil Science Society of America.Book series. No. 5 America Society Agronomy and Soil Science Society of America Madison, W1. Page 255-293.
• IITA 1979. Selected Methods for Soil and Plant Analysis. 2nd Edition, International Institute of Tropical Agriculture, Ibadan, Oyo State, Nigeria, Pp: 70.
• Jaiyeoba I.A. 2003. Changes in soil properties due to continuous cultivation in Nigerian semiarid Savannah. Soil & Tillage Research 70(1), 91-98.
• Kadiri W. O. J., Ogunleye K. S., Fasina A. S. & Babalola T. S. 2021. Soil properties affecting soil organic carbon stock under different land use types in two agro-ecological zones of Nigeria. Agro-Science, 20(3), 12–22.
• Lal R. 2004. Soil carbon sequestration to mitigate climate change. Geoderma, 123, 1-22.
• Maniyunda L. M., Awwal Y. A. & Daudu C. K 2020. Land Degradation Assessment Along a Toposequence in Hayin Gada, Sub Humid Agroecological Zone, Kaduna State Nigeria. Nigerian Journal of Soil and Environmental Research. 19, 61-70
• Nelson D.W. & Sommers, L.E. 1982. Total carbon, organic carbon, and organic matter. InA.L. Page, R.H. Miller, and D.R. Keeney (eds.) Methods of soil analysis. Part 2.Chemical and microbiological properties. 2nded. Agronomy. 9, 539-579.
• Obigbesan G.O. & Amalu U.C. 1985. Impact of long-term fertilizer application on the soil properties of a commercial cassava farm. Paper presented at the ISSS meeting on Soil Fertility, Soil Tilth and Post Clearing Land Degradation in the Humid Tropics. 21-26th July. Ibadan, Nigeria.
• Ojanuga A.G. 2006. Agroecological zones of Nigeria Manual. Berding, F. And Chude, V.O. National Special Programme for Food Security (NSPFS) and FAO. 124 pp.
• Page A.L., Miller R.H. & Keeney D.R. (eds.) Methods of soil analysis. Part 2. Chemical and microbiological properties. 2nd edition. Agronomy. Monogram. 9. Agronomy Society of America and Soil Science Society of America, Madison, WI.
• Ren C., Liu S., Van Grinsven H., Reis S., Jin S., Liu H. & Gu B. 2019. The impact of farm size on agricultural sustainability. Journal of Cleaner Production. 220,357-367
• Rhoades J.D. 1982. Cation exchange capacity. In Page, A.L., Miller, R.H. and Keeney, D.R. (eds). Methods of Soil Analysis. Part 2 Agronomy Volume 9. Madison WI. Page 149-157.
• Sasu Doris Dokua (2023 November, 27) Undernourishment and food insecurity in the Nigerian population 2004-2022 [Infographic] Statista https://www.statista.com/statistics/1262212/undernourishment-and-food-insecurity-in-nigeria/
• Soil Science Division Staff 2017. USDA Soil Survey Manual. Ditzler C., Scheffe K. & Monger H.C. (eds). USDA Handbook 18. Government Printing Office, Washington, D.C.
• Thomas G.W. 1982. Exchangeable cations. In: Page Al, Miller RH, Keeney DR (eds) Methods of soil analysis. Part. American Society of Agronomy –Soil Science Society of American, Madison. 159-166
• Thornton P.K., Hoogenboom G., Wilkens P.W., Bowen W.T. 1995. A computer program to analyze multiple-season crop model outputs. Agronomy Journal 87, 131-136.
• Tully K., Sullivan C., Weil R. & Sanchez P. 2015. The State of Soil Degradation in Sub-Saharan Africa: Baselines, Trajectories, and Solutions. Sustainability 7, 6523-6552
• Ubuoh E. A., Ejekwolu C. C. & Onuigbo I. V. 2017. The effect of burnt and un-burnt land on soil physicochemical characteristics in Ekeya-Okobo Local Government Area, Akwa Ibom State, Nigeria. Journal of Applied Sciences and Environmental Management, 21(5), 923-929.
• United Nations, Department of Economic and Social Affairs, Population Division (2023 November, 27). World Population Prospects: The 2022 Revision. https://www.worldometers.info/world-population/nigeria-population/
• Valette J. & Ibanga, I.J. 1984. Detailed Soil Survey Report of Institute for Agricultural Research Farm, Samaru. Page 1-64