Crop-livestock Interactions Research Articles

Tailoring interventions through a combination of statistical typology and frontier analysis: a study of mixed crop-livestock farms in semi-arid Zimbabwe

Summary An innovative methodological approach combining statistical typologies and stochastic frontier analysis was applied to data collected from 1840 mixed crop-livestock farms in six districts of Zimbabwe, representative of semi-arid areas of the country. The average annual cereal production was 362 kg farm–1, and the average annual livestock offtake was 0.64 ± 1.32 Tropical Livestock Units (TLU) farm–1. Our results demonstrate there is scope to increase cereal and livestock production by 90.7% and 111.9% relative to current production levels, respectively, with more efficient use of existing resources and technologies. Rainfall was found to have a strong effect on cereal production, highlighting the need for climate-smart practices. Livestock mortality (0.59 ± 1.62 TLU farm–1) was found to be in the same order of magnitude as livestock offtake (0.64 ± 1.32 TLU farm–1). Cereal production was supported by livestock, demonstrating the importance of crop-livestock interactions in these mixed farming systems. Three farm types were identified in our analysis. Crop-oriented mixed farms (31%) are likely to be the ones most responsive to crop-specific interventions e.g., crop rotation and integrated pest management. Livestock-oriented mixed farms (34%) are likely to benefit the most from livestock-specific interventions, e.g., home feed. Mixed farms dependent on off-farm activities (36% of the sample) may require nutrition-sensitive and labour-saving sustainable intensification technologies to benefit from their limited resources. Reducing cattle mortality is a priority for all three farm types. The method proposed here could be adapted to other contexts characterized by heterogeneous farming populations to target interventions.

An Ecological Reading of Crop–Livestock Interactions—Gers, Southwestern France, 1950 to the Present

Mixed crop–livestock farming is usually considered to be beneficial for the environment, but the comprehensive characterisation of functional interactions between crops and livestock, and thus the assessment of their ecological relevance, remain problematic. In this article, we design a systemic reading grid focusing on the agricultural practices of crop–livestock interactions, which we organised in four groups according to the agronomic functions they fulfil and the ecological processes involved: (i) animals are used as a source of mechanical energy; (ii) rangelands and permanent grasslands, serving as a source of biomass to manage fertility, are spatially interwoven into the cultivated fields; (iii) on those cultivated fields, non-fodder crops are rotated/associated with fodder crops; (iv) the livestock consume locally produced fodder, grain and straw, and their excreta are spread on cultivated plots. Based on 86 interviews with retired and active farmers, we applied this grid to study the dynamics of crop–livestock integration in a small French agricultural region since 1950. We show that even though the number of mixed crop–livestock farms remains quite high, there has been a massive impoverishment of crop–livestock interactions within these farms. We discuss this trend and the contributions made by the reading grid.

Simulating the impact of crop–livestock interaction on crop performance using DSSAT

AbstractAn integrated crop–livestock system (ICL) can help with enhancing soil quality and crop productivity, ultimately increasing farm income. Field experiments that evaluated the impact of cover crops (CCs) and grazing on crop productivity have shown mixed results primarily because of a relatively short duration of the crop–livestock system. Dynamic crop models can help to simulate the long‐term impact of soils and crop management on crop yield. The objectives of the current study were to develop a simple simulation methodology for crop–livestock interaction using the Decision Support System for Agrotechnology Transfer (DSSAT) and to evaluate the performance of CC grazing on maize (Zea mays L.) production. Here, differences in pre‐ and postgrazing dry matter were used to determine the daily biomass consumption by livestock, and the in vitro dry matter digestibility (IVDMD) of the CCs was used to determine the amount of manure that is being returned to the soil during the grazing period. The data generated from the field experiments were used to calibrate and evaluate the cropping system model (CSM)‐CERES‐Maize of DSSAT. The index of agreement (d) for yield was 0.99 and 0.95, whereas relative root mean squared error (RRMSE) was 4.72 and 0.3% of the observed yield for calibration and evaluation, respectively. The trends in the field data were well represented by the simulated data. The current methodology provides evidence that crop modeling can be used to study ICLs, especially the crop–livestock interactions, by scientists and policy makers to help develop best management practices to increase yield and improve soil health.

Nitrogen metabolism of an Indian village based on the comparative agriculture approach: How characterizing social diversity was essential for understanding crop-livestock integration

ContextAddressing the environmental impact of agriculture requires a comprehensive analysis of the system at stake, and accounting for the social diversity (i.e. social groups involved in farming and relationships between them) is particularly important for designing efficient policies aimed at mitigating these impacts. However, the integration of this diversity in environmental assessments remains challenging, partly due to the lack of frameworks for combining data and concepts belonging to bio-technical and social sciences. ObjectiveIn this study, we aimed at assessing how the combination of the conceptual frameworks of comparative agriculture and territorial metabolism helps to better understand the environmental impacts of agriculture. In particular, we look at the crop-livestock integration as a possible way to reduce nitrogen losses from agriculture, and study how social diversity shapes this integration. MethodsCombining comparative agriculture and territorial metabolism frameworks, we carried out an intensive fieldwork in Petlad (Gujarat, India) organised in four steps so as to successively (i) capture farm diversity at the micro-regional level, (ii) build archetypes representing farming systems, (iii) assess nitrogen flows at farming systems' level and (iv) model nitrogen metabolism at village level. Results and conclusionsWe found that despite obvious potential, crop-livestock interactions were limited, accounting for minor nitrogen flows compared to the flow of inputs, mainly synthetic fertilisers and feed concentrates. The output flows, mainly tobacco, cereals and milk, were also low and most of the input nitrogen was lost to the environment (surplus of over 600 kg N/ha from the cropping system balance), contributing to pollution. While large subsidies for synthetic fertilisers had a role in the development of such huge surpluses, our study showed that this environmentally harmful situation was also influenced by the existing socio-economic conditions and social relations in Petlad. Most of the owners who had sufficient access to land (>1 ha) focused on the very profitable tobacco production and tended to abandon livestock, which they no longer needed either technically or economically. Conversely, households with low or no access to land were motivated to raise dairy animals, in order to supplement small incomes from crops, but faced difficulties in feeding them. We conclude that promoting crop-livestock integration as a potential lever to reduce nitrogen surplus would be unlikely to succeed in the presence of such a strong social lock-in. SignificanceConcurring with certain critiques of socio-ecological systems approaches, this result advocates for a better consideration of social diversity in the analysis of the environmental impacts of agriculture and in the design of interventions.

GRASSLAND AGRICULTURE IN CHINA—A REVIEW

<List> <ListItem><ItemContent> • Grassland-based livestock production systems cover large areas in China. </ItemContent></ListItem> <ListItem><ItemContent> • China is facing degradation of rangeland and has great shortage of forage. </ItemContent></ListItem> <ListItem><ItemContent> • Five types of mixed crop-livestock systems in China described. </ItemContent></ListItem> <ListItem><ItemContent> • Improving crop–livestock integration requires S&T and policy supports. </ItemContent></ListItem></List> <fig><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2095-7505-8-1-35/fase-20378-hfj-tu1.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2095-7505-8-1-35/FASE-20378-HFJ-tu1.tif"/></fig> Interactions between crops and livestock have been at the core of the evolution of many agricultural systems. In this paper, we review the development and characteristics of mixed crop-livestock systems, with a focus on grassland-based systems, as these cover large areas in China, and face several challenges. Following the transition from the original hunting and foraging systems to a sedentary lifestyle with integrated crop-livestock production systems some 8000 years ago, a range of different mixed systems have developed, depending on rainfall, solar radiation and temperature, culture and markets. We describe 5 main types of integrated systems, (1) livestock and rangeland, (2) livestock and grain production, (3) livestock and crop – grassland rotations, (4) livestock, crops and forest (silvo-pasture), and (5) livestock, crops and fish ponds. Next, two of these mixed systems are described in greater detail, i.e., the mountain-oasis-desert system and its modifications in arid and semi-arid regions, and the integrated crop-livestock production systems on the Loess Plateau. In general, crop-livestock interactions in integrated systems have significant positive effects on crop production, livestock production, energy use efficiency and economic profitability. We conclude that improved integration of crop-livestock production systems is one of the most important ways for achieving a more sustainable development of animal agriculture in China.

Mulching is the most important of the three conservation agriculture principles in increasing crop yield in the short term, under sub humid tropical conditions in Zimbabwe

Some smallholder farmers in Sub Saharan Africa (SSA) have failed to adopt all the three principles of conservation agriculture (CA) because of various reasons including lack of alternative weed management methods (soil tillage), crop-livestock interactions (crop residue mulch used as livestock feed) and poorly developed markets for other crops (diversified cropping system). Studies have shown that smallholder farmers incorporate one or two CA principles, not all three, at a time in their cropping systems. Our study sought to disaggregate the effects of the three CA principles on crop growth with or without mineral fertilizer in order to determine which principle or combination of principles resulted in highest yield increase in the short to medium term. The research was conducted over four cropping seasons at Hunyani Farm located in Zvimba district in north western Zimbabwe characterized by sub humid tropical conditions and fine sandy loam soils. A split-split-plot design, with tillage as the main plot, mulch as the sub plot, rotation as the sub-sub plot and fertility regime as the treatments was used. Fertility treatments were control (no fertilizer added) and 120 kg N ha−1+ 30 kg P ha-1 +15 kg K ha−1 mineral fertilizer and the experiment was replicated three times. Reduced tillage increased maize grain yield from the third season when compared with mouldboard ploughing. The positive effects of mulching were higher when fertilizer was applied (>90 %) compared with no fertilizer application. Crop rotation (maize-soybean) had no significant effects on grain and aboveground dry matter yield. The benefits of the three CA principles on crop yield followed the order mulch > reduced tillage > crop rotation. The combined effects of the three CA principles on maize grain yield were higher than conventional tillage and any other one or two principles together indicating the importance of integrating the three principles for best results.

A framework to assess the economic vulnerability of farming systems: Application to mixed crop-livestock systems

The main challenge for farmers is to maintain a high annual income within an ever-changing context of production (climate, prices, sanitation issues), i.e. to ensure low vulnerability. The vulnerability of a given system corresponds to its susceptibility to be harmed, reflecting its inability to cope with adverse effects. This paper presents a framework that can be applied to determine the economic vulnerability of farming systems considering their social dimension, and to identify farming management profiles that are likely to be less vulnerable. The framework defines vulnerability levels based on analysis of four quantitative indicators reflecting the ‘behaviour’ of the economic results per labour unit in the long term: the relative standard deviation of the economic result per worker, the relative mean distance of the economic result to a minimum threshold, the number of economic disruptions over a specified period, and the economic recovery time after disruption. The framework was applied to a sample of 208 French farms, and the results revealed that diversification alone is not enough to cope with risks. Less vulnerable mixed crop-livestock systems are characterized by more crop-livestock interactions, allowing for less dependency on markets and more flexibility. This kind of management allows farms to be larger and to have more livestock. These findings help clarify the vulnerability of farming systems and may encourage the development of policies to enhance market opportunities at the regional level to foster diversification strategies and flexibility.

A participatory method for the design and integrated assessment of crop-livestock systems in farmers’ groups

Crop-livestock integration promises more sustainable farming systems, but is constrained by organizational and technical issues at the farm level. Developing locally-adapted crop-livestock systems between specialized farms remains theoretical due to a lack of methods for their design and of analysis of benefits and limits for their monitoring. This article presents a method for participatory design and assessment of territorial crop-livestock systems and its application to a group of organic farmers specialized in crop or livestock production in southwestern France. We developed an adapted assessment framework for territorial crop-livestock systems. We used it firstly to produce a diagnosis of strengths and weaknesses of farming systems then to identify the potential for new crop-livestock interactions between farms and finally we designed and assessed crop-livestock integration scenarios with farmers. The technical and organizational options for change were selected to satisfy objectives of partners, illustrated by specific performance criteria (biological regulation, work management economic viability, social learning and capacity building, embeddedness of agriculture in the territory, integration in public policies). This study shows the crucial role of an adaptive methodology that includes ad hoc indicators to support the design of sustainable farming systems that considers specific agroecosystem, constraints and objectives of farmers.

A social-ecological framework for analyzing and designing integrated crop–livestock systems from farm to territory levels

AbstractIntegrated crop–livestock systems are often considered a promising way to address agricultural sustainability issues. Many authors claim that complementarities and synergies between crops and livestock can improve nutrient cycling and delivery of ecosystem services (ES) in agricultural systems. They have analyzed effects of interactions at the farm level and affirmed the potential advantage of developing crop–livestock interactions at the territory level. However, potential benefits of developing synergies beyond the farm level have not been clearly identified. Thus, we developed a conceptual framework that can be used to analyze, design and perform integrated assessment of crop–livestock systems at the territory level. To address crop–livestock interaction issues, we define it as a social-ecological system called the territorial crop–livestock system (TCLS). The ecological system is represented as three interacting components, crops, grasslands and animals, allowing description of various land uses and their potential effects on nutrient cycling and ES. The social system, represented as farmers interacting with natural-resource managers and agro-food chain actors, determines land use and the nature and intensity of ES delivered. We highlight the importance of coordination and learning among actors to support implementation of complex adaptive systems such as TCLSs. We illustrate the expressive power of our conceptual framework through development of a generic typology of crop–livestock systems. Then we show how our conceptual framework can be used as an intermediary object with stakeholders in participatory design approaches. We illustrate this process by representing four archetypal TCLSs. We provide an example of the design approach implemented in Southwestern France to address severe recurrent water shortages, which includes analysis of land use in the current crop–livestock system and the associated key metabolic and ES issues, identification of options for change and multi-criteria analysis of these options. We conclude that this framework shows great potential to support development of sustainable farming systems at the territory level.

Direct and indirect impacts of crop–livestock organization on mixed crop–livestock systems sustainability: a model-based study

Crop–livestock production is claimed more sustainable than specialized production systems. However, the presence of controversial studies suggests that there must be conditions of mixing crop and livestock productions to allow for higher sustainable performances. Whereas previous studies focused on the impact of crop–livestock interactions on performances, we posit here that crop–livestock organization is a key determinant of farming system sustainability. Crop–livestock organization refers to the percentage of the agricultural area that is dedicated to each production. Our objective is to investigate if crop–livestock organization has both a direct and an indirect impact on mixed crop–livestock (MC–L) sustainability. In that objective, we build a whole-farm model parametrized on representative French sheep and crop farming systems in plain areas (Vienne, France). This model permits simulating contrasted MC–L systems and their subsequent sustainability through the following indicators of performance: farm income, production, N balance, greenhouse gas (GHG) emissions (/kg product) and MJ consumption (/kg product). Two MC–L systems were simulated with contrasted crop–livestock organizations (MC20–L80: 20% of crops; MC80–L20: 80% of crops). A first scenario – constraining no crop–livestock interactions in both MC–L systems – permits highlighting that crop–livestock organization has a significant direct impact on performances that implies trade-offs between objectives of sustainability. Indeed, the MC80–L20 system is showing higher performances for farm income (+44%), livestock production (+18%) and crop GHG emissions (−14%) whereas the MC20–L80 system has a better N balance (−53%) and a lower livestock MJ consumption (−9%). A second scenario – allowing for crop–livestock interactions in both MC20–L80 and MC80–L20 systems – stated that crop–livestock organization has a significant indirect impact on performances. Indeed, even if crop–livestock interactions permit improving performances, crop–livestock organization influences the capacity of MC–L systems to benefit from crop–livestock interactions. As a consequence, we observed a decreasing performance trade-off between MC–L systems for farm income (−4%) and crop GHG emissions (−10%) whereas the gap increases for nitrogen balance (+23%), livestock production (+6%) – MJ consumption (+16%) – GHG emissions (+5%) and crop MJ consumption (+5%). However, the indirect impact of crop–livestock organization doesn’t reverse the trend of trade-offs between objectives of sustainability determined by the direct impact of crop–livestock organization. As a conclusion, crop–livestock organization is a key factor that has to be taken into account when studying the sustainability of mixed crop–livestock systems.

Finding the right compromise between productivity and environmental efficiency on high input tropical dairy farms: A case study

This study focused on the trade-off between milk production and its environmental impact on greenhouse gas (GHG) emissions and nitrogen surplus in a high input tropical system. We first identified the objectives of the three main stakeholders in the dairy sector (farmers, a milk cooperative and environmentalists). The main aim of the farmers and cooperative's scenarios was to increase milk production without additional environmental deterioration but with the possibility of increasing the inputs for the cooperative. The environmentalist's objective was to reduce environmental deterioration. Second, we designed a sustainable intensification scenario combining maximization of milk production and minimization of environmental impacts. Third, the objectives for reducing the eco-inefficiency of dairy systems in Reunion Island were incorporated in a framework for activity analysis, which was used to model a technological approach with desirable and undesirable outputs. Of the four scenarios, the sustainable intensification scenario produced the best results, with a potential decrease of 238 g CO2-e per liter of milk (i.e. a reduction of 13.93% compared to the current level) and a potential 7.72 L increase in milk produced for each kg of nitrogen surplus (i.e. an increase of 16.45% compared to the current level). These results were based on the best practices observed in Reunion Island and optimized manure management, crop–livestock interactions, and production processes. Our results also showed that frontier efficiency analysis can shed new light on the challenge of developing sustainable intensification in high input tropical dairy systems.

Crop–livestock interactions: implications for policy-makers and for farmers

This paper was prepared in response to a paper prepared by Vetter (in this issue) that addressed the issue of policy development related to sustainable management of rangelands. In line with the sentiments of Vetter, policies are understood to guide the allocation of resources. The important contribution that livestock make to rural livelihoods is well recognised and strengthening crop–livestock interactions is seen as an effective way of improving livestock productivity while generally being understood as an effective way to increase agricultural production so as to meet the growing needs of the global population. The use of crop residues by livestock is one specific linkage that offers opportunities, but this could be maximised by increasing the yield and quality of the residues. One key challenge to strengthening crop–livestock interactions is the extent to which arable lands are being abandoned. Efforts need to be made to reverse this situation, which requires a range of technical and social/institutional interventions. Although some policy documents refer to integrated systems and alternative cropping practices, there is limited evidence that this in fact is happening on the ground. Policy needs to support crop–livestock interactions more actively so that on-farm research with farmers, as is happening in Msinga, becomes more widespread.

ECONOMIC EFFECTIVENESS OF THE CROP-LIVESTOCK INTERACTIONS IN FUNCTION OF ORGANIC PRODUCTION

The recent research has provided insight into the item whether livestock must be included in the crop farm in order to attain the economic benefits of crop-livestock interactions, particularly those related to soil fertility management. Crop-livestock operations are well suited to the adoption of many alternative practices. Crop rotations using cover crops, such as leguminous hays, are readily suited to livestock operations. These rotations reduce fertilizer and pesticide needs and provide a valuable feed source. Many legumes are quality hay crops. In croplivestock operations, hay crops with a market value ordinarily lower than cash grains have economic value as a portion of farm land in a cover crop. They may provide additional erosion control benefits and allow the planting of feed grains on more suitable land. Manure also becomes a valuable source of soil organic matter, nitrogen and other nutrients such as potassium and phosphorus. Diversified crop-livestock operations also have greater protection against input (feed) and output (animal products) price fluctuations. By different methods of calculations in this paper economic benefits in the interaction of cropping and livestock as well as the effects of the crop rotations on the farm will be analyzed.

Competing use of organic resources, village-level interactions between farm types and climate variability in a communal area of NE Zimbabwe

In communal areas of NE Zimbabwe, feed resources are collectively managed, with herds grazing on grasslands during the rainy season and mainly on crop residues during the dry season, which creates interactions between farmers and competition for organic resources. Addition of crop residues or animal manure is needed to sustain agricultural production on inherently poor soils. Objectives of this study were to assess the effect of village-level interactions on carbon and nutrient flows, and to explore their impact on the long-term productivity of different farm types under climate variability. Crop and cattle management data collected in Murewa Communal area, NE Zimbabwe was used together with a dynamic farm-scale simulation model (NUANCES-FARMSIM) to simulate village-level interactions. Simulations showed that grasslands support most cattle feed intake (c. 75%), and that crop residues produced by non-cattle farmers sustain about 30% of the dry season feed intake. Removal of crop residues (0.3–0.4 t C ha −1 yr −1) from fields of non-cattle farmers resulted in a long-term decrease in crop yields. No-access to crop residues of non-cattle farmers increased soil C modestly and improved yields in the long-term, but not enough to meet household energy requirements. Harvest of grain and removal of most crop residues by grazing cattle caused a long-term decline in soil C stocks for all farm types. The smallest decrease (−0.5 t C ha −1) was observed for most fertile fields of cattle farmers, who manure their fields. Cattle farmers needed to access 4–10 ha of grassland to apply 3 t of manure ha −1 yr −1. Rainfall variability intensifies crop–livestock interactions increasing competition for biomass to feed livestock (short-term effect) or to rehabilitate soils (long-term effect). Prolonged dry seasons and low availability of crop residues may lead to cattle losses, with negative impact in turn on availability of draught power, affecting area under cultivation in consecutive seasons until farmers re-stock. Increasing mineral fertiliser use concurrently with keeping crop residues in fertile fields and allocating manure to poor fields appears to be a promising strategy to boost crop and cattle productivity at village level. The likelihood of this scenario being implemented depends on availability of fertilisers and decision of farmers to invest in rehabilitating soils to obtain benefits in the long-term. Adaptation options cannot be blind to what occurs beyond field and farm level, because otherwise recommendations from research and development do not fit the local conditions and farmers tend to ignore them.

Crop–livestock interactions along agro-ecological gradients: a meso-level analysis in the Indo-Gangetic Plains, India

Although conceptually simple and often idealized, disentangling crop–livestock interactions typically proves more complex in practice. Part of the complexity arises from their changing nature along agricultural intensification gradients. Such interactions increase in scope when extensive systems intensify, but decline in importance as already intermediate systems intensify further. This changing nature of crop–livestock interactions in relation to the system’s developmental stage implies that these exchanges can both contribute but also undermine system sustainability. We examine crop–livestock interactions in the Indo-Gangetic Plains as an empirical case, drawing from village surveys to explore and illustrate these relations and implications along the agro-ecological gradient of this vast and important eco-region. Such an understanding is increasingly needed as adapting crop residue management practices is recognized as the key to address sustainability concerns in the prevailing rice–wheat systems and as a stepping stone towards conservation agriculture. The agricultural R&D community needs to incorporate this understanding more proactively into its R&D agenda if it is to succeed in sustaining productivity gains, improving rural livelihoods equitably, and securing environmental sustainability.

Beyond resource constraints – Exploring the biophysical feasibility of options for the intensification of smallholder crop-livestock systems in Vihiga district, Kenya

During participatory prototyping activities in Vihiga, western Kenya, farmers designed what they considered to be the ideal farm [Waithaka, M.M., Thornton, P.K., Herrero, M., Shepherd, K.D., 2006. Bio-economic evaluation of farmers’ perceptions of viable farms in western Kenya. Agric. Syst. 90, 243–271]: one in which high productivity is achieved through optimising crop-livestock interactions. We selected four case study crop-livestock farms of different resource endowment (Type 1–4 – excluding the poorest farmers, Type 5, who do not own livestock) and quantified all relevant physical flows through and within them. With this information we parameterised a dynamic, farm-scale simulation model to investigate (i) current differences in resource use efficiencies and degree of crop-livestock interactions across farm types; and (ii) the impact of different interventions in farm Types 3 and 4 on producing the desired shifts in productivity towards the ideal farm. Assuming no resource constraints, changes in the current farm systems were introduced stepwise, as both intensification of external input use (fertilisers and fodder) and qualitative changes in the configuration of the farms (i.e. changing land use towards fodder production, improving manure handling and/or changing cattle breeds). In 10-year simulations of the baseline, current scenario using historical weather data the wealthiest farms Type 2 achieved food self-sufficiency (FSS) in 20% of the seasons due to rainfall variability, whereas the poorer Type 4 only achieved FSS in 0 to 30% of the seasons; soil organic C decreased during the simulations at annual rates of −0.54, −0.73, −0.85 and −0.84 t C ha −1 on farms of Type 1–4, respectively; large differences in productivity and recycling efficiency between farm types indicated that there is ample room to improve the physical performance of the poorer farms (e.g. light and water use efficiency was 2–3 times larger on wealthier farms). Simulating different intensification scenarios indicated that household FSS can be achieved in all farm types through input intensification, e.g. using P fertilisers at rates as small as 15 kg farm −1 season −1 (i.e. from 7 to 28 kg ha −1). Increasing the area under Napier grass from c. 20 to 40% and reducing the area of maize, beans and sweet potato in farms of Type 3 and 4 increased their primary productivity by c. 1 t ha −1 season −1, their milk production by 156 and 45 L season −1, respectively, but decreased the production of edible energy (by 2000 and 250 MJ ha −1 season −1) and protein (by 20 and 3 kg ha −1 season −1). By bringing in a more productive cow the primary productivity increased even further in Farm Type 3 (up to 5 t ha −1 season −1), as did milk production (up to c. 1000 L season −1), edible energy (up to c. 10,000 MJ ha −1 season −1) and protein (up to c. 100 kg ha −1 season −1). The impact of livestock management on the recycling of nutrients and on the efficiency of nutrient use at farm scale can be large, provided that enough nutrients are present in or enter the system to be redistributed. An increase in N cycling efficiency through improved manure handling from 25 to 50% would increase the amount of N cycled in the case study farms of Type 1 and 2 by only ca. 10 kg season −1, and only 1–2 kg season −1 in Type 3 and 4. The various alternatives simulated when disregarding resource constraints contributed to narrow the productivity and efficiency gaps between poorer and wealthier farms. However, the feasibility of implementing such interventions on a large number of farms is questionable. Implications for system (re-)design and intensification strategies are discussed.

Crop–livestock interactions in agricultural and pastoral systems in West Africa

Driven by population pressures on natural resources, peri-urban pastoralists in the Far North Province of Cameroon have recently intensified livestock production in their traditional pastoral system by feeding their cattle cottonseed cakes and other agricultural byproducts to cope with the disappearance of rangelands typically available through the dry season. Although the crop–livestock interactions in this altered intensive pastoral system seem similar to alterations recently named in mixed-farming systems in West Africa, they are distinctly different and would require a different type of agricultural development support. I use Bourdieu’s theoretical constructs of “habitus” and “capital” to explain those differences.

Crop–Livestock Interactions in the West African Drylands

Many semiarid regions of Sub‐Saharan Africa (SSA) are experiencing vast increases in human population pressure and urbanization. These augment the demand for agricultural products and have led to the expansion, intensification, and often closer integration of crop and livestock production systems. The transition of crop and livestock production from the current relatively extensive, low input/output modes of production to more intensive, higher input/output modes of production presents numerous challenges to the achievement of required long‐term production increases from these farming systems. This paper provides an overview of the challenges facing agricultural production in semiarid SSA with a focus on West Africa. A description of mixed crop–livestock farming systems and their evolution is followed by an overview of the principal linkages between crops and livestock: income, animal power, feed, and manure. The most detailed discussions relate to nutrient cycling in these farming systems. Most livestock derive their feed almost exclusively from natural rangeland and crop residues, and livestock manure is a precious soil fertility amendment. However, most farmers have insufficient livestock and therefore manure to sustain food production. Nutrient harvests from cropland often exceed nutrient inputs, and soil nutrient depletion is a principal concern. The paper concludes with a discussion of strategies that may improve the productive capacity of these mixed farming systems.

Factors Affecting Farm-specific Production Efficiency in the Savanna Zones of West Africa

Agricultural intensification involving greater crop–livestock interactions and integration is emerging as the most promising strategy for improving agricultural production and productivity in much of Sub-Sahara Africa. In West Africa, where this process is at various stages of evolution, 559 farm households from the Sudan Savanna (SS) and Northern Guinea Savanna (NGS) zones were studied to examine the factors affecting production efficiency. The farms in each zone were divided into four socioeconomic domains using a combination of population density and market access as criteria. Estimation of stochastic frontier production function indicated the need to include ecological and socioeconomic variables in both the production function and the accompanying inefficiency equation, failing which such models may suffer from omitted variables bias. The results showed that inefficiency effects of a stochastic nature existed among the sample farms and average efficiency was 76%: 68% in the SS and 86% in the NGS zones. Further, increased resource use associated with agricultural intensification was not always accompanied by an increase in production efficiency; and while agricultural intensification based on high external input strategies yields higher marginal returns in the NGS, a similar strategy is not critical to success in the SS given

Crop–Livestock Interactions in the West African Drylands

Many semiarid regions of Sub-Saharan Africa (SSA) are experiencing vast increases in human population pressure and urbanization. These augment the demand for agricultural products and have led to the expansion, intensification, and often closer integration of crop and livestock production systems. The transition of crop and livestock production from the current relatively extensive, low input/output modes of production to more intensive, higher input/output modes of production presents numerous challenges to the achievement of required long-term production increases from these farming systems. This paper provides an overview of the challenges facing agricultural production in semiarid SSA with a focus on West Africa. A description of mixed crop–livestock farming systems and their evolution is followed by an overview of the principal linkages between crops and livestock: income, animal power, feed, and manure. The most detailed discussions relate to nutrient cycling in these farming systems. Most livestock derive their feed almost exclusively from natural rangeland and crop residues, and livestock manure is a precious soil fertility amendment. However, most farmers have insufficient livestock and therefore manure to sustain food production. Nutrient harvests from cropland often exceed nutrient inputs, and soil nutrient depletion is a principal concern. The paper concludes with a discussion of strategies that may improve the productive capacity of these mixed farming systems.