Research Article

The vertical mobility of nitrogen with poultry and sheep manures amendment on degraded Ultisols in Owerri, Southeastern Nigeria

HABEEBAH SAKA1*, Bethel Ugochukwu Uzoho2, Solomon Oladimeji Olagunju3, Musiliat Mopelola Onaolapo4
1 Department of Soil Science and Land Management, Federal University of Agriculture, Abeokuta, Ogun State, Nigeria
2 Department of Soil Science and Technology, P.M.B 1526, School of Agriculture and Agricultural Technology, Federal University of Technology, Owerri, Imo State, Nigeria.
3 Department of Crop Production, Faculty of Agricultural Production and Renewable Resources, P.M.B 2022, Olabisi Onabanjo University, Ogun State, Nigeria.
4 Department of Soil Science and Land Management, College of Plant Science and Crop Production, Federal University of Agriculture, P.M.B 2240 Abeokuta, Ogun State, Nigeria
* Corresponding author: sakaha@funaab.edu.ng
Published: May, 2026
DOI: 10.67042/njss.2026.9vd0xwaq
Pages: 203-221
Views: 140
Downloads: 70

Abstract

A randomized complete block design experiment was conducted for two years, two locations per year and three months per location with three replications. The rates of dried, milled pure poultry and sheep manures incorporated per location at the onset of the research were 0, 30 and 60 % N. Initial soils and manures were analyzed for macro nutrients. Soil samples collected weekly, bi-weekly and monthly at soil depths (0 – 5, 5 – 10, 10 – 20 and 20 – 40 cm) for (1st, 2nd, 3rd, 4th, 6th, 8th and 12th weeks) were analyzed for total nitrogen (g kg-1) using standard procedures. Applied poultry and sheep manures increased soil total N compared with control. Across the soil depths, soil total N contents decreased. Highest application of manures improved soil total N with the trend of P60S30 > P60S0 > P30S0 > P60S60. Consequently, this research revealed that addition of poultry and sheep manures at 60 and 30 % N improved the soil total N. Further research is recommended to check this fact.

Keywords

Poultry manure sheep manure total nitrogen dynamics Ultisols Owerri

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How to Cite

SAKA, H., Uzoho, B. U., Olagunju, S. O., & Onaolapo, M. M. (2026). The vertical mobility of nitrogen with poultry and sheep manures amendment on degraded Ultisols in Owerri, Southeastern Nigeria. Nigerian Journal of Soil Science, 35(1), 203-221. https://doi.org/10.67042/njss.2026.9vd0xwaq

H. SAKA, B. U. Uzoho, S. O. Olagunju, and M. M. Onaolapo, "The vertical mobility of nitrogen with poultry and sheep manures amendment on degraded Ultisols in Owerri, Southeastern Nigeria," Nigerian Journal of Soil Science, vol. 35, no. 1, pp. 203-221, May 2026. doi: 10.67042/njss.2026.9vd0xwaq

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