Efficient fertilizer use

Efficient fertilizer use can contribute to increase crop yields, efficient energy use in agriculture and reduced pollution. Most (89%) of the increased agricultural production over the coming decades is expected to come from agricultural intensification, bringing along more intensive use of fertilizer. In several regions, nutrient limitations set the major ceiling on yields (Bindraban et al., 1999; Breman et al., 2001). Fertilizer use is particularly low in many parts of Africa and this constrains land and water productivity (in sub-Saharan Africa, only 9kg/ha of external nutrients are used as compared to 73kg/ha used in Latin America, 10 kg/ ha in South Asia and 135 kg/ha in East and Southeast Asia) (Kelly 2006). Therefore, particularly in sub-Saharan Africa, the world’s major agricultural frontier, a system of sustainable intensification is advocated (Pretty et al., 2006; Pretty et al. 2011; Tilman et al. 2011). With current rainfall patterns, improved soil fertility could double productivity in Africa (Molden et al., 2010), particularly if the appropriate dose and right type of fertilizer (responding to soil deficiencies, as can be evaluated by soil testing) are used. It is important is that fertilizers are used efficiently, as overuse contributes to influxes of nitrogen and phosphorus. These are negatively affecting many Earth systems in the form of groundwater pollution, eutrophication, reduced or depleted oxygen in water bodies causing extinction of species and land degradation (Rockström et al., 2009).

Bio-fertilizers and other nutrient sources, if properly used, are often a credible alternative to chemical fertilizers. Bio-based fertilizers more over help to improve the soil structure – a very important advantage. They also have the advantage of being produced locally – generating job opportunities. There are several types of bio-based fertilizer:

– Organic manure

– Compost

– Vermicompost

– Green manuring

– Bio-fertilizer

References:

Bindraban, P.S., Verhagen, A., Uithol, P.W.J., Henstra, P., 1999. A Land Quality Indicator for Sustainable Land Management: The Yield Gap. Report 106. Research Institute Agrobiology and Soil Fertility, Wageningen, The Netherlands.

Breman, H., Groot, J.J.R., van Keulen, H., 2001. “Resource limitations in Sahelian agriculture”. Global Environmental Change 11(1), 59-68.

Kelly, V.A., 2006. Factors Affecting Demand for Fertilizers in sub-Saharan Africa. Agriculture and Rural Development Discussion Paper 23. The World Bank, Washington, DC.

Molden, D., Oweis, T., Steduto, P. Bindraban, M.A. Hanjra, M.A., Kijne, J. 2010. “Improving agricultural water productivity: between optimism and caution”. Agricultural Water Management 97(4), 528-535.

Pretty J., Noble, A.D., Bossio, D., Dixon, J., Hine, R.E., Penning de Vries, F.W.T., Morison, J.I.L., 2006. Resource conserving agriculture increases yields in developing countries. Environmental Science and Technology 3(1), 24-43.

Pretty, J.N., Toulmin, C., Williams, S., 2011. “Sustainable Intensification in African Agriculture”. International Journal of Agricultural Sustainability 9, 5-24.

Rockström, J., Steffen, W., Noone, K., Persson, A., Chapin, III, F.S., Lambin, E. Lenton, T.M. Scheffer, M.et al., (2009). “Planetary Boundaries: Exploring the Safe Operating Space for Humanity”. Ecology and Humanity 14(2), 32.

Tilman, D., Balzar, C. Hill, J. Befort, B.L. 2011. “Global food demand and the sustainable intensification of agriculture”. Proceedings of the National Academy of Sciences of the United States of America 108(50), 20260-20264.