Agriculture In Southern Africa Research Articles

Comparing the financial benefits of different grain production systems in South Africa’s summer rainfall region

There is growing evidence that soil degradation, among other factors, has led to both the decline and constraint of agriculture in southern Africa. Conservation and regenerative agriculture (CA/RA) have been proposed as a grain crop production system that could slow down, halt or even reverse some of these disturbing trends. But the question remains whether it is financially viable. We sought to find an answer to this question by comparing the financial returns of a CA/RA system over a 20-year period to its alternatives, namely conventional tillage (CT) and no-tillage (NT) production systems. The cumulative free cash flow (CFCF) of the average between the realistic and conservative CA/RA scenarios in year 20 is considerably higher than that of the other systems under investigation. The CFCF for CA/RA in year 20 in Mpumalanga is estimated to be R86 million, compared to -ZAR51 million for CT and about ZAR4 million for NT. That is a net difference between ZAR137 million (compared to CT) and ZAR82 million (compared to NT). In the Maluti area, the CFCF for the CA/RA production system is estimated at ZAR26 million, compared to -ZAR66 million for CT and -ZAR19 million for NT. In the North-West production area, the CFCF for the CA/RA production system is estimated at ZAR35 million, compared to -ZAR9 million for CT and about ZAR21 million for NT. The differences between the CFCF of the CA/RA system and the other systems represent the financial opportunity cost of not converting to the CA/RA system.

Prospects for Organic Farming in Coping with Climate Change and Enhancing Food Security in Southern Africa: A Systematic Literature Review

The potential for organic farming (OF) as a system that enhances climate change (CC) adaptation and improves food security in Africa has been a provocative topic in global discussions. Although OF is promptly increasing globally, the pertinent question is to figure out how OF can result in sustainable food production systems. This systematic literature review was undertaken through two database searches to maximize available data and relevant literature (Scopus and Wiley Online Library), resulting in 2069 documents published between 2007 and 2022. After excluding documents that were duplicates, not presented in English and irrelevant, 538 documents remained. From the remaining documents, 406 were excluded after careful review (not meeting at least one of the inclusion criteria), and 132 documents remained. Finally, 95 documents were excluded after assessing and reviewing full-text articles for eligibility. As a result, 37 documents were included (eligible) in the systematic review. The inclusion criteria followed in this study considered language, thematic focus and document type. The reviewed articles suggest that OF can be one of the climate change adaptation options, preserve environmental impact and improve food security. However, the relative performance in OF differs from region to region. Correspondingly, the organic–conventional yield gap mostly depends on crops and cropping practices. This review concludes the prospects of organic agriculture in Southern Africa are still largely untapped, particularly by smallholder farmers who remain uncertified. Therefore, the review recommends organised interventions on various fronts, starting with organic certification and regulation. Accordingly, sustainability (economic, environmental and social) and investments in OF need to be reinforced and promoted by stakeholders, as it has the potential to alleviate the swarming farming challenges posed by climate change and to address food insecurity.

On-farm agronomic performance and farmer preference of quality protein maize grown under conservation agriculture in Southern Africa: a case for Zimbabwe

AbstractMaize is the most important staple food crop in southern Africa with human consumption averaging 91 kg/capita/year. Most smallholder farmers and weaning children depend on maize for much of the daily food requirements and it is the largest contributor of dietary proteins. Despite the development of quality protein maize (QPM) with high tryptophan and lysine content, stunting and kwashiorkor remain high in southern Africa partly due to low adoption of QPM varieties. The objective of this study was to compare the agronomic performance and farmer preferences of new generation of QPM with non-QPM varieties under conservation agriculture on-farm conditions. Eight QPM and four non-QPM varieties were tested on on-farm trials in Zimbabwe during the 2014/15 and 2015/16 cropping seasons at five different locations. Significant differences were detected among the genotypes for the measured traits in the two seasons. Similarly, genotype plus genotype × environment interactions were significant for both seasons for grain yield. Three QPM varieties, SC527, SC535 and SC643, recorded the highest and stable yield. Four QPM varieties, SC643, SC535, SC527 and MQ623, and a non-QPM variety, PAN413, were ranked high among farmers for overall ear characteristics as their most preferred varieties. The high-yielding and stable QPM varieties are likely to be adopted by farmers in southern Africa.

Richard A. Sikora, Eugene R. Terry, Paul L. G. Vlek and Joyce Chitja (eds): Transforming agriculture in southern Africa: Constraints, technologies, policies and processes

Richard A. Sikora, Eugene R. Terry, Paul L. G. Vlek and Joyce Chitja (eds): Transforming agriculture in southern Africa: Constraints, technologies, policies and processes

Prospects for Long-Term Agriculture in Southern Africa: Emergent Dynamics of Savannah Ecosystems from Remote Sensing Observations

Hydro-climatic resilience is an essential element of food security. The miombo ecosystem in Southern Africa supports varied land uses for a growing population. Albedo, Leaf Area Index (LAI), Fractional Vegetation Cover (FVC), Solar-Induced chlorophyll Fluorescence (SIF), and precipitation remote-sensing data for current climate were jointly analyzed to explore vegetation dynamics and water availability feedbacks. Changes in the surface energy balance tied to vegetation status were examined in the light of an hourly albedo product with improved atmospheric correction derived for this study. Phase-space analysis shows that the albedo’s seasonality tracks the landscape-scale functional stability of miombo and woody savanna with respect to precipitation variations. Miombo exhibits the best adaptive traits to water stress which highlights synergies among root-system water uptake capacity, vegetation architecture, and landscape hydro-geomorphology. This explains why efforts to conserve the spatial structure of the miombo forest in sustainable farming of seasonal wetlands have led to significant crop yield increases. Grass savanna’s high vulnerability to water stress is illustrative of potential run-away impacts of miombo deforestation. This study suggests that phase-space analysis of albedo, SIF, and FVC can be used as operational diagnostics of ecosystem health.

Potential for Sustainable Mountain Farming: Challenges and Prospects for Sustainable Smallholder Farming in the Maloti–Drakensberg Mountains

Achieving sustainable food security is a critical goal for smallholder farmers in mountainous regions around the world. In the 40,000 km2 Maloti–Drakensberg mountains (South Africa and Lesotho), one of the important mountain ranges of southern Africa, farmers are directly dependent on natural resources. Natural resource management is currently unsustainable, driving landscape degradation and entrenching poverty cycles. Through a comprehensive literature review, we explore the current status of knowledge, opportunities, and agriculture-dependent natural resource sustainability in the Maloti–Drakensberg, and outline the priorities for future research in mountain agriculture in southern Africa. The Maloti–Drakensberg has diverse land tenure systems and climatic heterogeneity that together determine farming practices. Agropastoralism is the predominant agricultural practice, occupying 79% of the land, because of the natural grass-dominated vegetation. Despite decades of concern, the sustainable management of communal rangeland remains elusive. Arable cropping is practiced on 12% of the land at subsistence levels, while game farming contributes a small amount to local revenues. A multipronged research approach is needed to understand the complex social–ecological issues around soil degradation and sustainable utilization of the limited agricultural natural resources base. Innovative and adaptive strategies that take into account local and indigenous knowledge, mitigate soil degradation, and enhance water and rangeland conservation are needed to promote sustainable food production in the Maloti–Drakensberg.

Public spending on agriculture in Southern Africa: Sectoral and intra-sectoral impact and policy implications

The purpose of this paper is two-fold: firstly, it examines the relationship between public agriculture expenditure and agriculture sector growth, and secondly, it examines the heterogeneous effects of expenditure on agriculture growth depending on which subsectors within agriculture receive the investments. The co-integration analysis results offer insights into a number of issues: (i) it is found that agricultural expenditures are important for agriculture sector growth in Malawi, Eswatini (Swaziland) and Zambia and (ii) that within the agricultural sectors, investing in research and development, subsidies, and in neglected areas (livestock, fisheries) alongside crops can expand the agricultural sector more. Policy makers should increase public spending in agriculture but should also emphasize on improving intra-sectoral allocations, targeting areas that create sectoral growth.

Poverty and Agriculture in Southern Africa Revisited: A Panel Causality Perspective

Agricultural advancement is considered a panacea for poverty reduction, particularly, in developing countries. This study empirically investigates the dynamic linkage between agricultural value added (AVA) and poverty reduction for a panel of nine countries in Southern Africa using a second-generation panel approach for the period 1990 to 2015. Empirical results show that agricultural development is necessary but not a sufficient policy to combat poverty as it is only viable in the short run. Thus, we suggest long-run economic programs and/or strategies that will complement agricultural development toward poverty alleviation to spur economic growth in the sampled region.

Prospects for Improving Irrigated Agriculture in Southern Africa: Linking Water, Energy and Food

Increasing agricultural productivity has always been a prominent feature on the regional agenda due to a high incidence of food and nutrition insecurity. This review assessed the current status of irrigated agriculture in southern Africa from a water–energy–food (WEF) nexus perspective. Gaps and opportunities for improving irrigated agriculture within the context of the WEF nexus were also assessed in terms of the feasible limits to which they can be exploited. Southern Africa faces water scarcity, and climate projections show that member states will face increased physical and/or economic water scarcity by as early as 2025, which will have negative impacts on water, energy and food production. Recurrent droughts experienced across the region reaffirm the sensitive issues of food and energy insecurity as well as water scarcity. Projections of an increasing population within the region indicate increased water, energy and food demand. With agriculture already accounting for about 70% of water withdrawals, increasing the area under irrigation will place additional demand on already strained energy grids and scarce water resources. This poses the question—is increasing irrigated agriculture a solution to improving water access, food security and energy supply? While there are prospects for increasing the area under irrigation and subsequent improvement in agricultural productivity, adopting a WEF nexus approach in doing so would mitigate trade-offs and unintended consequences. Consideration of the WEF nexus in integrated resources planning and management eliminates the possibilities of transferring problems from one sector to other, as it manages synergies and trade-offs. While it is acknowledged that improving water productivity in irrigated agriculture could reduce water and energy use while increasing yield output, there is a need to decide how such savings would then be reallocated. Any intervention to increase the irrigated area should be done in the context of a WEF nexus analytical framework to guide policy and decision-making. Technical planning should evolve around the WEF nexus approach in setting targets, as WEF nexus indicators would reveal the performance and impact of proposed interventions on any of the three WEF nexus components.

A glance at achievements of SASAS and animal scientists in southern Africa over more than 50 years

With the congress theme of ‘Golden Innovations for Sustainable Animal Agriculture’, it would be opportune to look not only at innovations with present and future potential, but at those ‘golden innovations’ that have been achieved and established over more than five decades. Many of these innovations still form the basis of many aspects of present-day sustainable animal agriculture in southern Africa. This brief review covers three areas, namely the history of the South African Society for Animal Science (SASAS), achievements of animal scientists, mainly in the earlier years of the Society, and the coming of age of professionalism in the animal science profession. The South African Society of Animal Production (SASAP) was founded on 28 April 1961 in Pretoria. The name was later changed to the South African Society for Animal Science. The theme of the first congress of SASAP was ‘Efficiency in Production’, a theme that is still relevant. In 1971 the South African Journal of Animal Science (SAJAS) was initiated, and by 2017 the 47th volume has been published. A large amount of knowledge that is applicable to local conditions has accumulated and should be drawn upon to avoid ‘reinventing the wheel’. In the 1950s to 1970s, Professor Jan Bonsma developed the concept of functional efficiency of cattle and principles that focused on adaptability and sustainability. Extensive research was conducted on the feeding of urea and phosphorus to grazing livestock, leading to the practice of urea-containing rumen-stimulating winter supplementation of ruminants. South Africa was considered a world leader in the field of supplementary feeding practices. South Africa has a proud history in the discipline of animal genetics and the practical application of breeding principles to enhance livestock productivity, and is in the forefront with studies on the genomics of livestock in southern Africa. SASAS was instrumental in establishing the professional status of animal scientists in South Africa. The vision is that an animal scientist should be identified as the expert in his/her field and the best qualified person to advise on matters such as animal breeding, nutrition and general management of livestock. SASAS council also acts as a mouthpiece for and custodian of animal scientists. The society protects the interests of animal scientists, is pro-active in promoting animal science, and acts as a watchdog over the professional activities of members. Keywords: Animal production, history, professional animal scientist

Uncertainty of Rainfall Products: Impact on Modelling Household Nutrition from Rain-Fed Agriculture in Southern Africa

Good quality data on precipitation are a prerequisite for applications like short-term weather forecasts, medium-term humanitarian assistance, and long-term climate modelling. In Sub-Saharan Africa, however, the meteorological station networks are frequently insufficient, as in the Cuvelai-Basin in Namibia and Angola. This paper analyses six rainfall products (ARC2.0, CHIRPS2.0, CRU-TS3.23, GPCCv7, PERSIANN-CDR, and TAMSAT) with respect to their performance in a crop model (APSIM) to obtain nutritional scores of a household’s requirements for dietary energy and further macronutrients. All products were calibrated to an observed time series using Quantile Mapping. The crop model output was compared against official yield data. The results show that the products (i) reproduce well the Basin’s spatial patterns, and (ii) temporally agree to station records (r = 0.84). However, differences exist in absolute annual rainfall (range: 154 mm), rainfall intensities, dry spell duration, rainy day counts, and the rainy season onset. Though calibration aligns key characteristics, the remaining differences lead to varying crop model results. While the model well reproduces official yield data using the observed rainfall time series (r = 0.52), the products’ results are heterogeneous (e.g., CHIRPS: r = 0.18). Overall, 97% of a household’s dietary energy demand is met. The study emphasizes the importance of considering the differences among multiple rainfall products when ground measurements are scarce.

Complementary practices supporting conservation agriculture in southern Africa. A review

Conservation agriculture (CA)—the simultaneous application of minimum soil disturbance, crop residue retention, and crop diversification—is a key approach to address declining soil fertility and the adverse effects of climate change in southern Africa. Applying the three defining principles of CA alone, however, is often not enough, and complementary practices and enablers are required to make CA systems more functional for smallholder farmers in the short and longer term. Here, we review 11 complementary practices and enablers grouped under six topical areas to highlight their critical need for functional CA systems, namely: (1) appropriate nutrient management to increase productivity and biomass; (2) improved stress-tolerant varieties to overcome biotic and abiotic stresses; (3) judicious use of crop chemicals to surmount pest, diseases, and weed pressure; (4) enhanced groundcover with alternative organic resources or diversification with green manures and agroforestry; (5) increased efficiency of planting and mechanization to reduce labor, facilitate timely planting, and to provide farm power for seeding; and (6) an enabling political environment and more harmonized and innovative extension approaches to streamline and foster CA promotional efforts. We found that (1) all 11 complementary practices and enablers substantially enhance the functioning of CA systems and some (e.g., appropriate nutrient management) are critically needed to close yield gaps; (2) practices and enablers must be tailored to the local farmer contexts; and (3) CA systems should either be implemented in a sequential approach, or initially at a small scale and grow from there, in order to increase feasibility for smallholder farmers. This review provides a comprehensive overview of practices and enablers that are required to improve the productivity, profitability, and feasibility of CA systems. Addressing these in southern Africa is expected to stimulate the adoption of CA by smallholders, with positive outcomes for soil health and resilience to climate change.

Strengthening mutual accountability and performance in agriculture in Southern Africa


 
 
 We critically assessed experiences in the implementation of agricultural joint sector reviews in supporting mutual accountability in Southern Africa, focusing on the lessons learned, the challenges and recommendations for improvement. Empirical data were gathered from four countries that have implemented joint sector reviews: Malawi, Mozambique, Swaziland and Zambia. The results show that recent efforts to conduct joint sector review assessments in these countries have raised the quest for increased accountability for action and results. Despite progress to strengthen mutual accountability in the countries, monitoring and evaluation capacity remains a concern, especially at sub-national levels. The mutual accountability process and implementation of the agricultural joint sector review processes in the respective countries have come a long way in facilitating sector-wide engagement of stakeholders in planning, implementation and monitoring and evaluation of agricultural policies and programmes. These processes are critical to ensure effective implementation and realisation of development impacts of agricultural priorities in the national agricultural investment plans.
 
 
 
 
 Significance: 
 
 
 
 The implementation of the CAADP mutual accountability framework is critical to ensure effective implementation and realisation of development impacts of agricultural priorities in the national agricultural investment plans.
 Agriculture joint sector reviews facilitate sector-wide engagement of stakeholders in planning, implementation, and monitoring and evaluation of agricultural policies and programmes.
 
 
 

Factors Affecting Adoption of Agroforestry and Evergreen Agriculture in Southern Africa

This paper examines the factors that affect adoption of agroforestry and integrated soil fertility management (ISFM) practices in Southern Africa. Agroforestry practices, especially evergreen agriculture and conservation agriculture with trees have emerged as sustainable measures of addressing land degradation and loss of soil fertility. Although agroforestry is known to be beneficial to farmers and the environment, its adoption rate falls far behind the projected goals. The present study reviewed several publications on adoption of agroforestry in Southern Africa and complemented the review with household and key informant interviews to obtain evidence from farmers and promoters of the technologies on the factors affecting adoption. The study revealed that the major factors affecting adoption of agroforestry fall into two main categories of socioeconomic and biophysical factors. The factors are high initial costs of agroforestry practices (75%), low extension knowledge (69%); unavailability of agroforestry germplasm (69%) for economic, social and biophysical categories respectively. Up to 84% of the key informants indicated that awareness of the connection between agroforestry and land quality improvement could lead to wide scale adoption of the technology. We conclude that Government policies will strongly influence adoption of agroforestry technologies. There is need to institutionalise sustainable agricultural land management practices through policy formulation, budgetary allocation for extension officers and farmer training and starter up inputs. Promotion of agroforestry should be coupled with investment in awareness creation, farmer-centered approaches in selection of technology and provision of inputs in the initial stages. Strong collaboration among policy makers, researchers and extension providers will be required to harmonise messages to be delivered to farming communities.

Local impacts of climate change and agronomic practices on dry land crops in Southern Africa

Climate change impact assessments on agriculture in Southern Africa are mostly carried out at large spatial scales, risking missing out on local impacts and adaptation potential that reflect the range of multiple and unique bio-physical and agronomic conditions under which farmers in the region operate. This study investigated how climate change may affect yields of various major food crops in specific locations in the region; maize and sorghum (Mohale’s Hoek – Lesotho and Big Bend – Swaziland), maize and groundnut (Lilongwe – Malawi). Using statistically downscaled climate projections from nine GCMs and the DSSAT crop model and simulating selected agronomic strategies practiced in each location, the study confirmed that impacts of climate change on crop yields in Southern Africa vary across locations and crops. Despite various uncertainties associated with such assessments, the results showed that crop yields were predominantly projected to decline in Big Bend (maize (−20%); sorghum (−16%)) and Lilongwe (maize (−5%); groundnut (−33%)). However, crop yields in Mohale’s Hoek, located in a high altitude region historically prone to cold related crop yield losses were on average projected to increase (maize (+8%) and sorghum (+51%)). The geographical variation of yield projections highlights the importance of location specific climate change impact assessments. The exploration of local agronomic management alternatives revealed prospects for identifying locally relevant adaptation strategies, which cannot easily be captured at larger scales.

Conservation agriculture in Southern Africa: Advances in knowledge

AbstractThe increasing demand for food from limited available land, in light of declining soil fertility and future threats of climate variability and change have increased the need for more sustainable crop management systems. Conservation agriculture (CA) is based on the three principles of minimum soil disturbance, surface crop residue retention and crop rotations, and is one of the available options. In Southern Africa, CA has been intensively promoted for more than a decade to combat declining soil fertility and to stabilize crop yields. The objective of this review is to summarize recent advances in knowledge about the benefits of CA and highlight constraints to its widespread adoption within Southern Africa. Research results from Southern Africa showed that CA generally increased water infiltration, reduced soil erosion and run-off, thereby increasing available soil moisture and deeper drainage. Physical, chemical and biological soil parameters were also improved under CA in the medium to long term. CA increased crop productivity and also reduced on-farm labor, especially when direct seeding techniques and herbicides were used. As with other cropping systems, CA has constraints at both the field and farm level. Challenges to adoption in Southern Africa include the retention of sufficient crop residues, crop rotations, weed control, pest and diseases, farmer perception and economic limitations, including poorly developed markets. It was concluded that CA is not a ‘one-size-fits-all’ solution and often needs significant adaptation and flexibility when implementing it across farming systems. However, CA may potentially reduce future soil fertility decline, the effects of seasonal dry-spells and may have a large impact on food security and farmers’ livelihoods if the challenges can be overcome.

Determination of amino acid contents of manketti seeds (Schinziophyton rautanenii) by pre-column derivatisation with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate and RP-HPLC

Defatted kernel flour from manketti seed kernels (Schinziophyton rautanenii) is an underutilised natural product. The plant grows in the wild, on sandy soils little used for agriculture in Southern Africa. The kernels are rich in protein and have a great potential for improving nutrition. The protein content and amino acid profile of manketti seed kernel were studied, using a new analytical method, in order to evaluate the nutritional value. The crude protein content of the press cake and defatted kernel flour was 29.0% and 67.5%, respectively. Leucine and arginine were found to be the most abundant essential and non-essential amino acids, respectively. The seed kernel contained 4.77g leucine and 12.34g arginine/100g of defatted seed kernel flour. Methionine and proline were the least abundant essential and non-essential amino acids to with 0.23g methionine and 0.36g proline/100g of defatted seed kernel flour, respectively. Validation of the pre-column derivatisation procedure with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) for the determination of amino acids was carried out. The analytical parameters were determined: linearity (0.0025–0.20mM), accuracy of the derivatisation procedure: 86.7–109.8%, precision (method: 0.72–5.04%, instrumental: 0.14–1.88% and derivatisation: 0.15–2.94% and 0.41–4.32% for intraday and interday, respectively). Limits of detection and quantification were 6.80–157mg/100g and 22.7–523mg/100g kernel flour, respectively.

The conundrum of conservation agriculture and livelihoods in Southern Africa

Low crop productivity, food insecurity, hunger and malnutrition; inadequate farming knowledge and skills, implements and inputs are characteristic of smallholder agriculture in Southern Africa. Many researchers argue that conservation agriculture can guarantee higher crop productivity, food security, improved livelihoods and environmental protection, better than the unsustainable traditional systems of slash and burn practices. In this paper, we present the results of a meta-analysis of over 40 academic publications to review conservation agriculture’s role in influencing desired livelihood outcomes in Southern Africa. We conclude that the effectiveness of conservation agriculture towards better livelihood outcomes in Southern Africa remains debatable, especially when supportive government policies are lacking.

Soyabeans and sustainable agriculture in southern Africa

Maize is the dominant staple crop across most of southern Africa—it is so dominant in some areas that more than 80 per cent of the smallholder land area is planted with maize. Soyabean was identified as the crop with a potential to address the need for diversifying the cropping systems, which could assist in overcoming the pervading soil fertility constraints and could provide smallholder farmers with an opportunity to earn income while also addressing the nutritional security of households. An initiative was launched in the 1996/97 cropping season in Zimbabwe, to test soyabean as a potential smallholder crop. From an initial 55 farmers in the first year, soyabean production expanded rapidly to an estimated 10,000 farmers three years later. Since then, soyabean has diffused spontaneously to most smallholder farming areas in the higher rainfall zones of Zimbabwe. Thus, the initiative has assisted a large number of smallholders to grow soyabean, and exploded a long-held belief in Zimbabwe that soyabean is not a suitable crop for smallholders.

Biodiversity boost to African crop

Summary A new study shows mixed planting can greatly boost maize yields. Nigel Williams reports.