Land use in Africa

With high and accelerating population growth and with low and declining efficiency in the use of resources, Africa is currently facing a long-term declining trend. Since agriculture accounted for 41% of the GDP of Africa in 1982, formulation and implementation of efficient land use policies are prerequisites if the long-term adverse trend is to be reversed.     

Land use policies and farming systems: Kenya, Tanzania, Zambia and Mozambique

Land use and farming systems are important considerations in the present African crisis. Evidence of land use problems in four selected African countries — Kenya, Tanzania, Zambia and Mozambique — and how these problems can be resolved are outlined. Policy options and recommendations available to the above four countries are analysed.     

Farmer perceptions of legumes and their functions in smallholder farming systems in east Africa

Legumes play an important role in sub-Saharan Africa (SSA) farming systems through the provision of food, feed, fuel, income and a range of biophysical benefits, such as soil fertility enhancement and erosion control. However, their full potential is not being realized. The purpose of this study was to assess farmers’ perceptions and knowledge towards legumes and the rationale of farmers for current legume production practices using a survey of 268 farmers in the Democratic Republic of Congo and Kenya. Most of the farmers had some knowledge of legumes and their characteristics. However, they had little knowledge of some key functions, including soil erosion control and soil fertility improvement. Most farmers relied on radio and other farmers for legume-related information. Farmers with relatively large livestock holdings ranked provision of livestock feed as an important legume function. We conclude that farmers put more value on short-term benefits of legumes including food and income than long-term benefits such as natural resource management and thus grain legumes are more readily identified by farmers than forage species. Also, we conclude that farmers require more than just information about legumes to increase uptake, they also require improved market access to procure inputs and sell products to realize other benefits that are associated with growing legumes.     

Land tenure systems and agricultural innovation: The case of alley farming in Nigeria

Alley farming is an agroforestry technology which requires access to land and the rights to plant, own and utilize trees. This paper considers the implications of land tenure systems in south-west and south-east Nigeria for the acceptability and viability of alley farming. Considerable variation in the rules governing the use and control of land is seen to exist within and between the two regions, and any one tenure system may include a number of categories of land to which different patterns of use and tenure apply. Broadly speaking, tenants in parts of south-west Nigeria may be disadvantaged as their rights over hired land do not necessarily include the right to plant trees. In the south-east, the existence of communal systems of landownership and management on some categories of land undermines the ability to plant trees and the incentive to invest labour in the maintenance of soil fertility.     

Measuring the sustainability and economic viability of tropical farming systems: a model from sub-Saharan Africa

New technologies must be developed in sub-Saharan Africa which are sustainable and economically viable. This paper discusses a methodology for measuring the agricultural sustainability and economic viability of tropical farming systems for new technology evaluation. The approach is based on the concept of interspatial and intertemporal total factor productivity, paying particular attention to valuation of natural resource stock and flows. Agriculture is a sector which utilizes natural resources (e.g. soil nutrients) and the stock and flows of these resources affect the production environment. However, in many cases, the stock of these resources is beyond the control of the farmer and must be accounted for in an agricultural sustainability and economic viability measurement. For example, soil nutrients are removed by crops, erosion or leaching beyond the crop root-zone, or other processes such as volatilization of nitrogen. Agricultural production can also contribute to the stock of some nutrients by leguminous plants such as agroforestry systems. Using a data set available at the International Institute of Tropical Agriculture, we compute the intertemporal and interspatial total factor productivity indices for four cropping systems in southwestern Nigeria using stock of major soil nutrients as the natural resource stock. Results show that the sustainability and economic viability measures are sensitive to changes in the stock and flow of soil nutrients as well as the material inputs and outputs. Where the contribution of natural resource stock and flows are important (such as in the case of alley cropping), the measures provide markedly different results from conventional TFP approaches. The advantage of this approach is that interspatial and intertemporal total factor productivity measures are computed using only price and quantity data, thus eliminating the need for econometric estimation.     

Integration of conservation agriculture in smallholder farming systems of southern Africa: identification of key entry points

A component-omission experiment based on the principle of conservation agriculture (CA) was established on smallholder farms for three seasons in Murehwa and Hwedza districts, Zimbabwe; Barue district in Mozambique; Balaka district and Chitedze Research Station in Malawi, and Monze district in Zambia to identify strategies for improving crop productivity and livelihoods for smallholder farmers. The objective of the experiment was to evaluate the effect of tillage, residue retention, fertiliser application and weed control on maize yield. In addition, the study analysed possible combinations of these factors that could provide a sustainable entry point for intensification through CA. Results showed that fertilisation had the strongest effect on crop yield in both tillage systems; adequate fertilisation is therefore key to success in CA. Retention of crop harvest residues increased yield in no-tillage systems; no-tillage without residues depressed yield by 50% when compared with yields of conventional tillage. A step-wise integration of CA into the smallholder farming systems is proposed as a possible strategy to avoid new constraints on smallholder farms. If resources are limiting, farmers may apply all principles on small areas to overcome the initial demand in resources (labour, fertiliser and residues), and once productivity is raised, they can expand.     

Land Reform in South Africa

An insightful study of the complexities of land reform in South Africa is reviewed, and its key arguments assessed. The study astutely combines ethnographic and historical detail from in-depth case studies in Mpumalanga Province with critical analysis of land reform policies, and locates these within larger theoretical debates on property rights, citizenship and identity. The author argues that a profound and unresolved tension exists within South Africa's land reform programme between broad and inclusive conceptions of 'rights' that are linked to notions of restored citizenship and sovereignty, and a conception of 'property' as individualized ownership of land, implying a much narrower conception of citizenship. The study also focuses on the roles of a variety of mediators and 'brokers' in land reform. Despite its many strengths, the study is not entirely convincing, partly because some key policy debates are mischaracterized. Its treatment of questions of agricultural production, rural livelihoods and the political economy of agrarian change is somewhat disappointing.     

Rural development and the role of game farming in the Eastern Cape,South Africa

The analysis of game farming is set in the Eastern Cape, South Africa. Game farming reorders the use, meaning and value of land and animal species. However, what it means for rural development processes in the immediate region and beyond is not well accounted for. We perceive game farming as an assemblage that brings together new actors, new forms of land use and new discourses. We argue that although game farming has generated new opportunities and new forms of added value to the available resources (e.g. eco-tourism, trophy hunting, game-meat production), situated in the history and contemporary context of the Eastern Cape, it is a contested, and from a development point of view, problematic land-use practice. We argue that game farming constrains land and agrarian reforms: the distribution of land and income remains skewed; ‘poaching’ occurs and game farms do not, or only minimally, generate new and badly needed employment opportunities. The game farm has emerged as an exclusive, globally well-connected space. The nature of the relationships this space maintains with the surrounding communities is, however, such that the overall contribution to rural development in South Africa is questionable.     

Factors influencing the use of alternative land cultivation technologies in Swaziland: Implications for smallholder farming on customary Swazi Nation Land

Poor land preparation and late planting are among the factors responsible for the decline in food production on customary Swazi Nation Land (SNL). While efforts are being made to develop an improved national land cultivation programme, this process can be helped by identifying factors that influence farmers to use alternative technologies for land cultivation. Using cross-section data collected in 2009 from a random sample of 210 farmers in Komati, three land cultivation technologies were identified; (i) use of tractors; (ii) use of draught animals; and (iii) use of hand hoes. For a country like Swaziland where human health problems, particularly HIV/AIDS, make manual labour a scarce resource, the use of tractors is regarded as a modern technology that can achieve time and labour savings. The empirical evidence from this study indicates that the use of tractors is significantly influenced by household wealth and size of arable land used by households. However, given that land holdings on customary land are generally small, sparsely distributed and often fragmented, tractor hire service providers face relatively high overhead and transaction costs. Furthermore, investment in mechanised farming by individual SNL households is constrained by the lack of secure tenure. Given these challenges, this study makes recommendations for creating an enabling environment that could promote the adoption of improved land cultivation methods by smallholders on customary SNL.     

Inequality and Social Conflict Over Land in Africa

The paper proposes that reports of pervasive competition and conflict over land in sub-Saharan Africa belie a current image of negotiable and adaptive customary systems of landholding and land use but, instead, reveal processes of exclusion, deepening social divisions and class formation. Cases of ambiguous and indeterminate outcomes among claimants over land do occur, but the instances of intensifying conflict over land, deepening social rifts and expropriation of land beg for closer attention. More emphasis needs to be placed by analysts on who benefits and who loses from instances of 'negotiability' in access to land, an analysis that, in turn, needs to be situated in broader political economic and social changes taking place, particularly during the past thirty or so years. This requires a theoretical move away from privileging contingency, flexibility and negotiability that, willy-nilly, ends by suggesting an open field, to one that is able to identify those situations and processes (including com-modification, structural adjustment, market liberalization and globalization) that limit or end negotiation and flexibility for certain social groups or categories.     

Improvement strategies for farming systems in the Eastern Highlands of Ethiopia

Eleven distinct farming systems were distinguished, based on selected indicators and locations. The indicators involve the resource basis, cropping pattern and intensity, and the major activities including off-farm work. Statistical tests were used to verify the differences. Accounting for the given constraints and for the interdependences of the system's components, strategies are developed to improve their poor economic performance. A linear programming model is used to evaluate the effects on farm performance of (a) reallocating the existing farm resources, and (b) introduction of improved technologies. The type of relationship among the elements of the farming system determines the overall outcome of any improvement effort. Groundnut and livestock production are highly competitive. A package of technological innovations is needed to achieve a major improvement on the smallest farms.     

Mixed farming in Africa: the search for order, the search for sustainability

This paper examines the interest in the development and promotion of mixed farming in sub-Saharan Africa. For over 70 years mixed farming has been a dominant model for agricultural development despite the limited success of many of the programmes which have specifically promoted it. It is suggested that the establishment of mixed farming as a strong development theme is related to its promise to address a range of environmental and social concerns, and in so doing, help create order out of a ‘chaotic’ African countryside. Mixed farming is again being highlighted with the more recent interest in sustainable, environmentally friendly agricultural systems. However, there is considerable evidence that African farmers have adopted a flexible principles-based approach to the use of component technologies commonly associated with the mixed farming model. This must be fully acknowledged, and the seduction of unitary models avoided, if agricultural research is to contribute efficiently to the development of more sustainable farming systems.     

Trade‐offs in the performance of alternative farming systems

Numerous alternative farming systems are proposed as solutions to the sustainability challenges of today's conventional farming systems. In this paper, we review the production, environmental, and socioeconomic performance of three widely discussed and promoted alternative farming systems—organic, smallholder, and urban agriculture. We show that both organic and smallholder agricultures have some benefits, but also entail important trade‐offs; organic has environmental benefits, and also livelihood, health, and nutritional benefits for producers and consumers, but is hampered by lower yields and higher prices. Smaller farms have higher yields and host higher biodiversity, but are hampered by lower incomes to farmers. Urban agriculture can take some pressure off rural landscapes, provide nutritional benefits to the urban poor, and engage urban dwellers in addressing food system challenges, but it simply cannot scale up to be a substantial solution in and of itself. We suggest that instead of focusing on alternative systems, we should identify pathways to sustainable farming for all systems, reforming conventional systems where they perform poorly, and transitioning to alternative systems in contexts where they perform best.     

The viability of cotton-based organic farming systems in India

Cotton farmers in many developing countries are facing decreasing marginal returns due to stagnating yields and high input costs. Conversion to organic management could offer an alternative. In a two year comparative study in central India covering 170 cotton fields, organic farms achieved cotton yields that were on par with those in conventional farms, whereby nutrient inputs and input costs per crop unit were reduced by half. Due to 10–20% lower total production costs and a 20% organic price premium, average gross margins from organic cotton fields were 30–40% higher than in the conventional system. Although the crops grown in rotation with cotton were sold without premium, organic farms achieved 10–20% higher incomes from agriculture. In addition to these economic benefits, the organic farming system does not burden soil and groundwater with synthetic fertilizers and pesticides. However, in this study only minor differences were detected in soil fertility parameters of organic and conventional fields. Altogether, the results suggest that conversion to organic farming can improve livelihoods of smallholders while protecting natural resources. Income loss due to reduced yields in initial years of transition, however, constitutes a major hurdle, especially for poorer farmers. It is thus important to support farmers in overcoming the obstacles of the conversion period.     

土壤微生物资源在农业中的开发和利用

土壤中存活大量微生物,它们和植物构成了微生物一植物系统,在这一系统中,微生物的作用不可忽视;论述了微生物在土壤中的存在环境,及其基本的分离鉴定方法,并且阐述了土壤微生物的作用,以及土壤微生物在农业中的应用情况和前景。     

Land use and climate change in the UK

This paper reviews the relationships between land use and climate change. It explores how land use decisions will be affected by future changes in the climate, but also the feedbacks from land use change to the global climate system through greenhouse gas (GHG) fluxes. Past changes in land use were characterised by decreasing areas of agricultural use and increasing areas of forested and urbanised land. This has led to UK land use being a net sink for GHGs, mostly due to forestation. However, existing forests have on average passed their age for maximum net removals of carbon from the atmosphere. In the next decade at least, net removals from UK forests are likely to decrease significantly.Longer term scenarios of future land use change are consistent in their expectation of further declines in the agricultural area used for food production – offset to some extent by increased bioenergy cropping – along with increases in forested and urban areas. These trends are broadly consistent with the observed past land use change, but are calculated from various assumptions about future changes in drivers rather than by extrapolation from the past. Socio-economic and technological changes are likely to be the most important drivers for land use, with climate change having a smaller influence. The land use changes represented in these scenarios would likely reduce GHG emissions and enhance carbon sinks. These trends would be reinforced by small future changes in the climate, but large climatic changes are likely to cause net GHG fluxes to switch from being a sink to a source. Land use change will also be moderated by potential policy goals that seek to reduce GHG emissions from land and/or increase the size of land-based sinks. This includes strategies to reduce carbon and nitrogen emissions through increased efficiency, afforestation and biofuel production.