Sustainable intensification options for smallholder maize-based farming systems in sub-Saharan Africa
- 993 Downloads
Appropriate sustainable intensification (SI) of agriculture is required in Sub-Saharan Africa to meet the rising demand for food and protect resources. Agroforestry and green manures, diversification with grain legumes, conservation agriculture and integrated nutrient management with mineral and organic fertilizers are SI options widely promoted for maize-based African smallholder systems. To assess the potential of SI options to contribute to multiple ecosystem services in these systems, we evaluated 17 published multi-year and site studies, using radar charts to systematically measure provisioning services (annualized maize grain and protein yields) and supporting services (vegetative biomass, rain productivity and agronomic efficiency of N fertilizer) among the studies and across technologies. We frequently observed trade-offs amongst provisioning and supporting ecosystem services, especially in rotational systems where the addition of a grain legume increased maize response to fertilizer but reduced annualized maize grain yields. Consistent gains in maize grain yield and vegetative biomass, and protein yield and rain productivity were obtained with the application of N fertilizer across the studies. More efficient use of N fertilizer was associated with legume diversification, particularly intercrop systems, with large incremental yield gains (30–80 kg grain kg−1 N fertilizer) at low fertilizer rates (< 50 kg N ha−1). These systems produced substantial amounts of grain, protein, vegetative biomass and high resource use efficiency (1 to 5-fold increase relative to sole maize). In contrast, performance was inconsistent from conservation tillage practices. The highly variable performance of many options that contribute to SI suggests the importance of their adaptation to local conditions and support for farmer innovation, rather than prescribing the use of fixed SI interventions. Overall, for maize system intensification, we suggest expanding farmer access to multipurpose legumes (such as long-duration pigeon pea) that provide food and copious biomass, and to N fertilizer, along with the local adaptation of water-conserving tillage practices.
KeywordsEcosystem services Sustainable agriculture Crop diversification Grain legume Green manure Agroforestry Mineral fertilizer Conservation tillage
We thank Emily May and Danielle Zoellner for help with literature citing and data preparation, as well as Regis Chikowo and five anonymous reviewers for their suggestions on drafts of this paper. A substantial part of the work was carried out while the lead author was affiliated with the International Food Policy Research Institute’s Malawi country program using funds from Irish Aid Malawi. Further financial support was provided by United States Agency for International Development - Feed the Future, through the Africa RISING project of the International Institute for Tropical Agriculture.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- Adjei-Nsiah, S., Kuyper, T. W., Leeuwis, C., Abekoe, M. K., & Giller, K. E. (2007). Evaluating sustainable and profitable cropping sequences with cassava and four legume crops: effects on soil fertility and maize yields in the forest/savannah transitional agro-ecological zone of Ghana. Field Crops Research, 103, 87–97.CrossRefGoogle Scholar
- Aguilera, Y., Diaz, M. F., Jimenez, T., Benitez, V., Herrera, T., Cuadrado, C., Martin-Pedrosa, M., & Martin-Cabrejas, M. A. (2013). Changes in nonnutritional factors and antioxidant activity during germination of nonconventional legumes. Journal of Agriculture and Food Chemistry, 61, 8120–8125.CrossRefGoogle Scholar
- Andersson, J. A., & Giller, K. E. (2012). On heretics and God’s blanket: contested claims for conservation agriculture and the politics of its promotion in African smallholder farming. In J. Sumberg & J. Thompson (Eds.), Contested agronomy: agricultural research in a changing world (pp. 22–46). New York: Routledge, Taylor and Francis Group.Google Scholar
- Boserup, E. (1965). The conditions of agricultural growth: the economics of agrarian change under population pressure. Chicago: Aldine.Google Scholar
- Bwalya, M., Diallo, A. A., Phiri, E., & Hamadoun, M. (2009). Sustainable land and water management: the CAADP Pillar1 framework. Midrand: The Comprehensive Africa Agriculture Development Programme (CAADP).Google Scholar
- Chuma, E., & Hagmann, J. (1995). Summary of results and experiments from on-station and on-farm testing and development of conservation tillage systems in semi-arid Masvingo. In S. Twomlow, J. Ellis-Jones, J. Hagmann, & H. Loos (Eds.), Soil and water conservation for smallholder farmers in semi-arid Zimbabwe: transfers between research and extension (pp. 61–69). Harare: Integrated Rural Development Programme.Google Scholar
- Dixon, J. A., Gulliver, A., & Gibbon, D. (2001). Farming systems and poverty: improving farmers’ livelihoods in a changing world (summary). In M. Hall (Ed.), Farming systems and poverty: improving farmers’ livelihoods in a changing world (p. 407). Rome: FAO & World Bank.Google Scholar
- Douxchamps, S., Rao, I. M., Peters, M., Van der Hoek, R., Schmidt, A., Martens, S., Polania, J., Mena, M., Binder, C. R., Scholl, R., Quintero, M., Kreuzer, M., Frossard, E., & Oberson, A. (2014). Farm-scale tradeoffs between legume use as forage versus green manure: the case of Canavalia brasiliensis. Agroecology and Sustainable Food Systems, 38, 25–45.CrossRefGoogle Scholar
- Fischer, G., Shah, M., Tubiello, F. N., & van Velhuizen, H. (2005). Socio-economic and climate change impacts on agriculture: an integrated assessment, 1990-2080. Philosophical Transactions of the Royal Society of London Series B, Biological Sciences, 360, 2067–2083.PubMedPubMedCentralCrossRefGoogle Scholar
- Funk, C., Dettinger, M. D., Michaelsen, J. C., Verdin, J. P., Brown, M. E., Barlow, M., & Hoell, A. (2008). Warming of the Indian Ocean threatens eastern and southern African food security but could be mitigated by agricultural development. Proceedings of the National Academy of Sciences of the United States of America, 105, 11081–11086.PubMedPubMedCentralCrossRefGoogle Scholar
- Gilbert, R. A. (2004). Best-bet legumes for smallholder maize-based cropping systems of Malawi. In M. Eilitta, J. Mureithi, & R. Derpsch (Eds.), Green manure/cover crop Systems of Smallholder Farmers: experiences from tropical and subtropical regions (pp. 153–174). Dordrecht: Kluwer.CrossRefGoogle Scholar
- Giller, K. E., Tittonell, P., Rufino, M. C., van Wijk, M. T., Zingore, S., Mapfumo, P., Adjei-Nsiah, S., Herrero, M., Chikowo, R., Corbeels, M., Rowe, E. C., Baijukya, F., Mwijage, A., Smith, J., Yeboah, E., van der Burg, W. J., Sanogo, O. M., Misiko, M., de Ridder, N., Karanja, S., Kaizzi, C., K’Ungu, J., Mwale, M., Nwaga, D., Pacini, C., & Vanlauwe, B. (2011b). Communicating complexity: integrated assessment of trade-offs concerning soil fertility management within African farming systems to support innovation and development. Agricultural Systems, 104, 191–203.CrossRefGoogle Scholar
- Haggblade, S., & Tembo, G. (2003). Early evidence on conservation agriculture in Zambia. A paper prepared for the international workshop on "reconciling rural poverty and resource conservation: identifying relationships and remedies". Ithaca: Cornell University.Google Scholar
- Jensen, J. R., Bernhard, R. H., Hansen, S., McDonagh, J., Moberg, J. P., Nielsen, N. E., & Nordbo, E. (2003). Productivity in maize based cropping systems under various soil-water-nutrient management strategies in a semi-arid, alfisol environment in East Africa. Agricultural Water Management, 59, 217–237.CrossRefGoogle Scholar
- Kibunja, C. N., Mwaura, F. B., Mugendi, D. N., Gicheru, P. T., Wamuongo, J. W., & Bationo, A. (2012). Strategies for maintenance and improvement of soil productivity under continuous maize and beans cropping system in the sub-humid highlands of Kenya: case study of the long-term trial at Kabete. In A. Bationo, B. Waswa, J. Kihara, I. Adolwa, B. Vanlauwe, & K. Saidou (Eds.), Lessons learned from long-term soil fertility management experiments in Africa (pp. 59–84). Dordrecht: Springer.CrossRefGoogle Scholar
- Kihara, J., Bationo, A., Mugendi, D. N., Martius, C., & Vlek, P. L. G. (2011). Conservation tillage, local organic resources and nitrogen fertilizer combinations affect maize productivity, soil structure and nutrient balances in semi-arid Kenya. Nutrient Cycling in Agroecosystems, 90, 213–225.CrossRefGoogle Scholar
- Kumwenda, J. D. T., Waddington, S. R., Snapp, S. S., Jones, R. B., & Blackie, M. J. (1996). Soil fertility management research for the maize cropping systems of smallholders in southern Africa: a review. Natural Resources Group Paper 96–02 (p. 35). Mexico DF: CIMMYT.Google Scholar
- Li, L., Li, S. M., Sun, J. H., Zhou, L. L., Bao, X. G., Zhang, H. G., & Zhang, F. S. (2007). Diversity enhances agricultural productivity via rhizosphere phosphorus facilitation on phosphorus-deficient soils. Proceedings of the National Academy of Sciences of the United States of America, 104, 11192–11196.PubMedPubMedCentralCrossRefGoogle Scholar
- Nyagumbo, I., & Bationo, A. (2011). Exploring crop yield benefits of integrated water and nutrient management technologies in the desert margins of Africa: experiences from semi-arid Zimbabwe. In A. Bationo, B. Waswa, J. M. Okeyo, F. Maina, & J. M. Kihara (Eds.), Innovations as key to the green revolution in Africa (pp. 759–772). Netherlands: Springer.CrossRefGoogle Scholar
- Okalebo, J. R., Othieno, C. O., Woomer, P. L., Karanja, N. K., Semoka, J. R. M., Bekunda, M. A., Mugendi, D. N., Muasya, R. M., Bationo, A., & Mukhwana, E. J. (2006). Available technologies to replenish soil fertility in East Africa. Nutrient Cycling in Agroecosystems, 76, 153–170.CrossRefGoogle Scholar
- Smith, L., Alderman, H., & Aduayom, D. (2006). Food insecurity in sub-Saharan Africa: new estimates from household expenditure surveys. Washington DC: International Food Policy Research Institute.Google Scholar
- Stroosnijder, L. (2007). Rainfall and Land Degradation. In Climate and land degradation. Berlin: Springer Berlin Heidelberg, pp. 167–195. Available at: http://link.springer.com/10.1007/978-3-540-72438-4_9.
- Twomlow, S., Rohrbach, D., Dimes, J., Rusike, J., Mupangwa, W., Ncube, B., Hove, L., Moyo, M., Mashingaidze, N., & Mahposa, P. (2010). Micro-dosing as a pathway to Africa’s green revolution: evidence from broad-scale on-farm trials. Nutrient Cycling in Agroecosystems, 88, 3–15.CrossRefGoogle Scholar
- Vissoh, P., Manyong, V. M., Carsky, J. R., Osei-Bonsu, P., & Galiba, M. (1998). Experiences with macuna in West Africa. In D. Buckles, A. Eteka, O. Osiname, M. Galiba, & G. Galiano (Eds.), Cover crops in West Africa contributing to sustainable agriculture. Ottawa: IDRC IITA, Ibadan; SG2000, Cotonou.Google Scholar
- Waddington, S.R., Sakala, W.D., & Mekuria, M. (2004). Progress in lifting soil fertility in Southern Africa. Proceedings of the 4th International Crop Science Congress, 26 September - 1 October, 2004. ICSC, Brisbane, Australia. http://www.cropscience.org.au/icsc2004.
- Waddington, S. R., Karigwindi, J., & Chifamba, J. (2007b). The sustainability of a groundnut plus maize rotation over 12 years on smallholder farms in the sub-humid zone of Zimbabwe. African Journal of Agricultural Research, 2, 342–348.Google Scholar