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Maintaining soil fertility in Africa

Declining soil fertility is a fragile base on which to build expectations for increased crop production and there is growing concern over soil degradation, particularly in Africa. Africa is where population and urbanization are increasing fastest and yet it is also where there appears to be the steepest decline in soil fertility. It is also where there is the most difficulty in providing supplementary plant nutrients due to the cost of fertilizers (including transport), even where they are available. However, opinions differ both on how critical is the situation and what are the realistic options for remedial actions. Readers of this Points of View are encouraged to send in their own comments.


"About two-thirds of Africans depend on agriculture for their livelihoods….As the region's population continues to grow rapidly, farmers are intensifying land use to meet food needs without proper management practices and external inputs. The resulting depletion of nutrients from soils has caused crop production to stagnate or decline in many African countries. Unless African governments, supported by the international community, take the lead in confronting the problems of nutrient depletion, deteriorating agricultural productivity will seriously undermine the foundations of sustainable economic growth in Africa."
IFPRI "Nutrient depletion in the agricultural soils of Africa" October '99

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"The Soil Fertility Initiative: sine qua non for boosting productivity. The Initiative seeks primarily to convince governments of African countries to create a favourable climate--in terms of credit facilities, land reforms and input accessibility--that will allow farmers to adopt sound management practices. Over the years, stupendous efforts have been made to bring the Green revolution to Africa. Yet, the magic that has worked in Asia and elsewhere in the world has somehow eluded Africa. According to the philosophy behind the Initiative, it is not lack of water but low soil fertility that is the limiting factor. In fact one can say, "fertilization is irrigation" because it has been found that soil improvement increases the water use efficiency of crops and leads to higher recovery of applied nutrients".
http://www.cgiar.org/icrisat/text/news/soil_fertility_initiative.htm

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"Although soil fertility is closely linked to the physical and chemical characteristics of the environment it must be recognised that it is strongly influenced by human management practices. Actually soil fertility is built up by rural communities through progressive and steady modification of the natural resource base (soils, vegetation, slopes, water flows…) by cropping fallowing, grazing, cutting and planting trees, selecting crop species, draining, irrigating, ploughing, sub-soiling, fertilizing, transferring crop residues and fodder. Soil fertility is also strongly influenced by the accumulation of organic wastes, ashes, night-soil and various by-products close to living areas and by the long term rotation of these living areas. Farmers need to be empowered through farmer's organizations which can contribute to the planning and implementation of improved practices, and which are fully involved in bidding for funds and in managing them toward more beneficial land management."
Alain Ange: CIRAD, France

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"Low external input agriculture is based on making better use of organic materials available on-farm to build up soil organic matter. This long term, labour intensive approach is often used to create small plots of high value land, or gardens. However, the low nutrient concentration of many organic materials means that a very large amount of material must be transported and applied to attain any reasonable yield. High levels of labour invested in transport and application are likely only to be feasible where the crops grown can fetch a good price, such as for vegetables around a major town."
Ian Scoones & Camilla Toulmin "Policies for soil fertility management in Africa" IDS

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"An evaluation of thirty years of development co-operation makes evident that the success in the field of sustainable land management is rather limited in sub-Saharan Africa. We have learned that farmers adopt new technologies, even when developed in a participatory manner, only when there is an inducive socio-economic, institutional and legal environment. Therefore we anticipate that the SFI (Soil Fertility Initiative) will be a valuable tool for assisting partner countries in defining limiting factors and creating a more favourable environment for long-term investments in soil fertility. However, we have the impression that the Initiative is too technically biased, i.e. researchers and developers still have the majority. More stakeholders need to be integrated, especially the agribusiness and farmers or farmer associations."
Kurt Steiner: GTZ

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"IFDC (International Fertilizer Development Centre) views the SFI as a tool to trigger agricultural intensification on the base of sustainable production systems. An important aspect of the SFI is policy reform, particularly those that provide incentives for the private sector to be competitive in the agricultural inputs and product markets. In this respect, IFDC is leading an initiative funded in part by USAID to develop a strategic framework for the development of sustainable agricultural inputs systems in sub-Saharan Africa. The collaborating institutions include fertilizer, seed and agro-chemicals trade institutions and associations, donors, research and development institutions, multinational companies, private sector input distributors, farmers, NGOs, and policy makers. The end product will be a framework that will guide donors and national governments in the design of projects and programmes that could contribute to the development of sustainable private sector agricultural input supply systems."
H.Breman and S.K.Debrah: IFDC (International Fertilizer Development Centre)

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"All communities identified land (expressed in terms of availability and/or fertility) as the main factor limiting production. The causes of soil infertility included shortage of manure, tillage practices, continuously cropping the same land, limited crop rotation, sand collection, indiscriminate cutting of trees, burning of crop residues and bush fires."
David Millar, CECIK, PO Box 607, Bolgatanga UER, Ghana writing in ILEIA Newsletter Sept.'99

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"Traditionally, widespread dry-season burning of vegetation was practised. Burning as a labour-saving tool to clear land and prevent weed infestation is now being brought into question, because more organic matter is needed in the soil. Many development agencies now advocate non-burning. Case studies of non-burning at Goziire (Upper West Region) and of non-burning and organic manuring at Zagsilaari (Northern Region) had suggested that these practices support sustainable agriculture by improving soil fertility and conserving soil and water. At Goziire, sorghum was taller after three year fallow than in the non-burnt plots. Millet in the non-burnt plots with farm yard manure was twice as tall as in the burnt plots with manure or without. Sorghum yields ranged from 1.1 to 1.4 t/ha and were higher after non-burnt fallow than after non-burnt continuous cropping, even with FYM. The success story of Goziire in this respect was a result of awareness creation that led the local people to mobilise themselves into a volunteer group to control fire. The community instituted locally endorsed by-laws. Culprits are sanctioned and must pay fines. The community also has the support of the Paramount Chief of Nandom to enforce the laws. The heightened awareness spread to surrounding villages, which have now also adopted non-burning."
O.I. Aalangdong et al, University of Development Studies, PO Box 1350, Tamale, Ghana writing in ILEIA Newsletter, Sept.'99

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"There are growing environmental concerns about maintaining or improving the natural resource base for agriculture. It has been estimated that since the 1950s, over 22 per cent of agricultural land worldwide has been degraded. Livestock undoubtedly contribute to these problems, but the allegations against livestock are often exaggerated or unfounded. For example in Central America although the area under pasture has almost tripled and livestock numbers have doubled over the past two decades, land degradation problems have been caused mainly by land speculation, corrupt titling procedures, and biased financial incentives rather than livestock production per se."
Simeon Ehui: IFPRI

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"To maintain current average levels of crop production without depleting soil nutrients, Africa will require approximately 11.7 million tons of NPK each year, roughly three times more than it currently uses (3.6 million tons). Burkina Faso would have to increase its NPK consumption more than 11 times to maintain production levels without depleting nutrients and Swaziland would have to double its consumption. Significant policy changes will be required to establish an environment that makes agricultural inputs easily available, that encourages farmers to use these inputs more efficiently, and that helps improve local extension services and farmer support."
IFPRI "Nutrient depletion in the agricultural soils of Africa" October '99

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"Soils in many parts of Africa are so lacking in nutrients--nitrogen and phosphorus in particular--that crop production has declined to an alarmingly low level. One solution is 'improved fallows', the planting of leguminous trees, which fix nitrogen from the air and transfer it to the soil, in land left fallow after cultivation. In rotation with maize, such fallows can accumulate between 100 and 150 kilograms of nitrogen per hectare, substantially increasing maize yields. Another solution tackles the problem of phosphorus deficiency. By combining and working into the soil an application of low-cost rock phosphate (from Tanzania) and a weedy shrub called tithonia, the problem disappears."
Online@ICRAF

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"The lack of three essential factors in most countries--adequate infrastructure, viable outlets, and alternative employment--creates unfavourable cost:benfit ratios for fertilizer and other external inputs. These factors together have led to the decline in soil fertility. The African governments have to wake up to the urgency of the problem and stimulate the involvement of the private sector in these areas, which will ultimately help solve the soil fertility problem."
http://www.cgiar.org/icrisat/text/news/soil_fertility_initiative.htm

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"Evidence for soil fertility decline stems from a few highly influential studies of land degradation in Africa, which have been quoted over and over again, in the process often losing much of the qualification surrounding the original study. Thus the FAO study of 1990 gives net losses for soils in sub-Saharan Africa estimated at 10kg N, 4kg P and 10kg K per hectare per year. Equally the Global Assessment of Soil Degradation (GLASOD) review reckons some 26% of dryland Africa to be suffering from various degrees of soil degradation. The significance and extent of such losses are judged to be of sufficient importance that action be taken, such as through recapitalization of soil fertility, a greatly increased use of inorganic fertiliser, and a more efficient recycling of biomass within the farming system. Yet examination of other evidence from more detailed field level studies demonstrates that the soil fertility problem is far more complex and diverse, prompting the need to recast the problem in a new light and suggesting alternative approaches to intervention….Global initiatives such as the Convention to Combat Desertification, and the Soil Fertility Initiative provide a means for getting attention paid to formerly neglected areas and themes. However, the very simplicity of the message they present--soil fertility in Africa is in serious decline--provides a misleading and potentially damaging assessment of what is happening, leading to the potential for poorly formulated interventions."
"Policies for soil fertility management in Africa" by Ian Scoones and Camilla Toulmin: IDS

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