OPTIMIZING AGRONOMIC-NITROGEN USE EFFICIENCY OF MAIZE PRODUCTION IN TANZANIA
Abstract
This study aimed at assessing different production functions for maize production in Tanzania. The maize yield performance, and agronomic – nitrogen use efficiency (AE) were evaluated under 6 rates of nitrogen (N) and water (W). Computations made for maize yield and AE shows that (i), the maximum potential maize yield increases with irrigation. (ii) less amount of fertilizer is needed to produce a unit of maize in the presence of high irrigation. Specifically, the maximum maize yield at 50 kg/ha of N is 6200 kg/ha and requires irrigation of 400mm, whereas at 100 kg/ha of N, the maximum yield is 5700 kg/ha and given 300mm of irrigation. Given the decrease in the fertilizer use efficiency, it implies that it is not plausible for farmers to apply optimum dose of nitrogen where there is water shortage. Moreover, two models, which are the quadratic function and the Mitscherlich-Baule function were fitted and compared based on a combination of agricultural, econometric and bioeconomic properties of the production process. The Mitscherlich-Baule function proved the best fit model. Results of the regression analysis shows that maize yield response to nitrogen (N) and water (W) exhibits diminishing returns. This suggests that when an extra unit of these input is added to the production process, less and less addition is observed in the total output. Based on the findings of this empirical study, it is plausible to recommend that farmers in the study area should be careful in applying the recommended dose of N where water is limited, because maize yield efficiency would not be maximized.
References
Adu, G. B., Alidu, H., Amegbor, I. K., Abdulai, M. S., Nutsugah, S. K., Obeng-Antwi, K., ... and Etwire, P. M. (2018). Performance of maize populations under different nitrogen rates in northern Ghana. Annals of Agricultural Sciences, 63(2), 145-152.
Babazadeh, H., Ardalani, H., Kisekka, I., and Hoogenboom, G. (2021). Simultaneous water, salinity and nitrogen stresses on tomato (Solanum lycopersicum) root water uptake using mathematical models. Journal of Plant Nutrition, 44(2), 282-295
Baijukya, F., Sabula L., Mruma S., Mzee, F., Mtoka, E., Masigo, J., Ndunguru, A. and Swai, E. (2020). Maize production manual for smallholder farmers in Tanzania. Ibadan, Nigeria: IITA.
Durodola, O. S., and Mourad, K. A. (2020). Modelling Maize Yield and Water Requirements under Different Climate Change Scenarios. Climate, 8(11), 127.
FAOSTAT. (2019). United Republic of Tanzania. www.fao.org.
Foster, T., and Brozovic, N. (2018). Simulating crop-water production functions using crop growth models to support water policy assessments. Ecological Economics, 152, 9-21. https://doi.org/10.1016/j.ecolecon.2018.05.019
Frederick A., Emmanuel K. Y., Rob J. and Dale H. (2015) Comparison of Crop Yield and Pollution Production Response to Nitrogen Fertilization Models, Accounting for Crop Rotation Effect, Agroecology and Sustainable Food Systems, 39:3, 245-275, DOI:10.1080/21683565.2014.967435
Giuliani, M., Li, Y., Castelletti, A., and Gandolfi, C., (2016). A coupled human1120 natural systems analysis of irrigated agriculture under changing climate. Water Resources Research 52, 6928–6947.
Hu, Z., and Du, X. (2018). Saddlepoint approximation reliability method for quadratic functions in normal variables. Structural Safety, 71, 24-32.
Jha, S.K.; Ramatshaba, T.S.; Wang, G.; Liang, Y.; Liu, H.; Gao, Y.; Duan, A (2019). Response of growth, yield and water use efficiency of winter wheat to different irrigation methods and scheduling in North China Plain. Agricultural Water Management. 217, 292–302
Kadigi, I. L., Richardson, J. W., Mutabazi, K. D., Philip, D., Mourice, S. K., Mbungu, W., ... and Sieber, S. (2020). The effect of nitrogen-fertilizer and optimal plant population on the profitability of maize plots in the Wami River sub-basin, Tanzania: A bio-economic simulation approach. Agricultural Systems, 185, 102948.
Kansal M.L., Nyamsha D. (2021) Challenges of Food Security in Tanzania: Need for Precise Irrigation. In: Pandey A., Mishra S., Kansal M., Singh R., Singh V.P. (eds) Hydrological Extremes. Water Science and Technology Library, vol 97. Springer, Cham. https://doi.org/10.1007/978-3-030-59148-9_25
Laudien, R., Schauberger, B., Makowski, D., and Gornott, C. (2020). Robustly forecasting maize yields in Tanzania based on climatic predictors. Scientific reports, 10(1), 1-12.
Liverpool-Tasie, L. S. O., Omonona, B. T., Sanou, A., and Ogunleye, W. O. (2017). Is increasing inorganic fertilizer use for maize production in SSA a profitable proposition? Evidence from Nigeria. Food policy, 67, 41-51.
Luhunga, P. M. (2017). Assessment of the impacts of climate change on maize production in the Southern and Western Highlands Sub-agro Ecological Zones of Tanzania. Frontiers in Environmental Science, 5, 51.
Popp, M. P., Ashworth, A. J., Moore Jr, P. A., Owens, P. R., Douglas, J. L., Pote, D. H., ... and Dixon, B. L. (2018). Fertilizer recommendations for switchgrass: Quantifying economic effects on quality and yield. Agronomy Journal, 110(5), 1854-1861.
Shen, X., Wang, G., Tilahun Zeleke, K., Si, Z., Chen, J., and Gao, Y. (2020). Crop Water Production Functions for Winter Wheat with Drip Fertigation in the North China Plain. Agronomy, 10(6), 876.
Thomas, A. H. (2020). Improving Crop Yields in Sub-Saharan Africa-What Does the East African Data Say? IMF Working Papers
Uwiringiyimana, T., Kusolwa, M. P., Mamiro, D. P., Umuhozariho, M. G., and Niyonzima, J. P. (2020). Performance of snap beans varieties in lowland of Morogoro in Tanzania. Rwanda Journal of Agricultural Sciences, 2(1), 97-102.
Weng, W., Cobourn, K. M., Kemanian, A. R., Boyle, K. J., Shi, Y., Stachelek, J., & White, C. (2020). Quantifying Co-Benefits of Water Quality Policies: An Integrated Assessment Model of Nitrogen Management (No. 2352-2020-634). Selected Paper prepared for presentation at the 2020 Agricultural & Applied Economics Association Annual Meeting, Kansas City, MO. July 26-28, 2020.
Xiong, W.; Tarnavsky, E (2020). Better Agronomic Management Increases Climate Resilience of Maize to Drought in Tanzania. Atmosphere 11(9):982. https://doi.org/10.3390/atmos11090982
Zou, H., Fan, J., Zhang, F., Xiang, Y., Wu, L., and Yan, S. (2020). Optimization of drip irrigation and fertilization regimes for high grain yield, crop water productivity and economic benefits of spring maize in Northwest China. Agricultural Water Management, 230, 105986.
