Assisting Smallholder Farmers in Mixed Crop-Livestock Systems to Understand the Potential Effects of Technologies and Climate Change through Participatory Modelling

Smallholder farming systems in the semi-arid areas of Zimbabwe are characterized by low production. This low production is not solely due to lack of technologies but is also due to a lack of integrating a diversity of viewpoints belonging to local, expert and specialized stakeholders during technology development. Participatory approaches combined with computer-based modelling are increasingly being recognized as valuable approaches to jointly develop sustainable agricultural pathways. The application of this integrated and iterative process in developing and evaluating the impact of interventions aimed at improving food and feed production is discussed. The process allows farmers to determine the impact of their decisions, evaluate new options and define realistic production and management options tailored to their particular circumstances. Scientists and other stakeholders in-turn learn more about the farmers’ decision-making process, input and managerial potentials as well as knowledge gaps

Maize–mucuna rotation: An alternative technology to improve water productivity in smallholder farming systems

Rain-fed crop production systems in the semi-arid tropics of Zimbabwe are characterized by low water productivity (WP), which is partly attributed to inherent low soil fertility, and further exacerbated by continuous cropping without addition of adequate organic and inorganic fertilizers due to unavailability and high costs. A simulation modeling approach was used to evaluate potential interventions that can be used as entry points to improve crop water productivity. Low-cost interventions that use locally available organic inputs were evaluated using the Agriculture Production Systems sIMulator (APSIM). The farmer practice (FP) was compared to interventions comprising manure application (MN) and maize–mucuna rotation (MMR). Their potential effects on crop water productivity, dynamics of soil organic carbon (SOC) and total nitrogen (TN) were assessed. Average maize grain water productivity was 0.32, 0.40 and 0.70 kg m−3 under the FP, MN and MMR treatments, respectively, while that of mucuna biomass (Mucuna pruriens) was 1.34 kg m−3. Cropping under the FP and MN treatments showed negative trends in SOC and TN over 30 years, with average losses ranging from 17 to 74 kg ha−1 yr−1 and 6 to 16 kg ha−1 yr−1, respectively. In contrast, the MMR treatment showed positive trends in both soil organic carbon (SOC) and total nitrogen (TN). The SOC and TN increased by 2.6–194 kg ha−1 yr−1 and 6–14 kg ha−1 yr−1, respectively. According to the simulation results it can be concluded that the MMR treatment can improve the water productivity of smallholder maize systems in the semi-arid areas of Zimbabwe under nutrient-depleted soil conditions and can also contribute to the building up of SOC and TN

Assisting smallholder farmers in mixed crop-livestock systems to understand the potential effects of technologies and climate change through participatory modeling

Smallholder farming systems in the semi-arid areas of Zimbabwe are characterized by low production. This low production is not solely due to lack of technologies but also due to a lack of integrating a diversity of viewpoints belonging to local, expert and specialized stakeholders during technology development. Participatory approaches combined with computer-based modeling are increasingly being recognized as valuable approaches to jointly develop sustainable agricultural pathways. The paper discusses the application of this integrated and iterative process in developing and evaluating the impact of interventions aimed at improving food and feed production. The paper concludes that the process allows farmers to determine the impact of their decisions, evaluate new options and define realistic production and management options tailored to their particular circumstances. While in-turn scientists and other stakeholders learn more about the farmers’ decision-making process, input and managerial potentials as well as knowledge gaps

Co‐designing the transitions towards integrated market oriented mixed farming systems in semi‐arid Zimbabwe

In semi‐arid Zimbabwe, multiple constraints impact maize‐based crop‐livestock systems creating a poverty trap. These barriers include low soil fertility, variable climates, weak knowledge support, and lack of markets. Conventional technical options are insufficient to improve smallholder livelihoods. Given the diversity in resource endowments and livelihood sources identifying intensification options that fit circumstances remains problematic. In this paper we demonstrate co‐designing approaches (i.e. with multiple stakeholders) for two sites i.e. Gwanda and Nkayi districts, of contrasting agro‐ecological potential. We engaged low, medium and high resource endowed farmers to (i) co‐design plausible improved scenarios that included incremental changes ‐ testing currently promoted technologies for crop‐livestock intensification and drastic change ‐ assuming that removing barriers will encourage investments towards resilient and profitable farming; and (ii) We quantified benefits and trade offs from alternative integrated actions using an integrated whole farm modelling approach (APSFArm‐LivSim‐TOAMD). At both sites incremental change options improved food security through better‐integrated cereal‐legume‐livestock systems; income effects were however limited. Drastic change options achieved more substantial improvements in productivity, food and income generation: farmers set more land in use, with more diversified forage, food and cash crops and adapted cultivars, organic and mineral fertilizer application, small‐scale mechanization for ploughing and product processing and improved livestock management. Packages tailored to farm situations had larger benefits on food security and income than blanket applications. Recommendations that take into account the socioeconomic context and policies are key and need to be communicated in more effective ways for enabling more sustainable futures for smallholders in Zimbabwe

Effects of climate change and adaptation on the livestock component of mixed farming systems: A modelling study from semi-arid Zimbabwe

Large uncertainties about the impacts of climate change and adaptation options on the livestock component of heterogeneous African farming systems hamper tailored decision making towards climate-smart agriculture. This study addressed this knowledge gap through the development and use of a dynamic modelling framework integrating climate, crop, pasture and livestock models. The framework was applied to a population of 91 farms located in semi-arid Zimbabwe to assess effects on livestock production resulting from climate change and management interventions. Climate scenarios representing relative “cool-wet”, “hot-dry” and “middle” conditions by mid-century (2040–2070) for two representative concentration pathways were compared with the baseline climate. On-farm fodder resources and rangeland grass production were simulated with the crop model APSIM and the pasture model GRASP respectively. The simulated fodder availability was used in the livestock model LIVSIM to generate various production indicators including milk, offtake, mortality, manure, and net revenue. We investigated the effects of two adaptation packages targeting soil fertility management and crop diversification and quantified the sensitivity to climate change of both current and improved systems. Livestock productivity was constrained by dry-season feed gaps, which were particularly severe for crude protein and caused by the reliance on rangeland grazing and crop residues, both of low quality in the dry season. Effects on grass and stover production depended on the climate scenario and the crop, but year-to-year variation generally increased. Relative changes in livestock net revenue compared to the baseline climate varied from a 6% increase to a 43% decrease, and the proportion of farmers negatively affected varied from 20% to 100%, depending on the climate scenario. Adverse effects of climate change on average livestock production usually coincided with increased year-to-year variability and risk. Farms with larger stocking density faced more severe feed gaps and were more sensitive to climate change than less densely stocked farms. The first adaptation package resulted in increased stover production and a small increase in livestock productivity. The inclusion of grain and forage legumes with the second package increased milk productivity and net revenues more profoundly by 30%. This was attributed to the alleviation of dry-season feed gaps, which also reduced the sensitivity to climate change compared to the current system. Clearly, individual farms were affected differently by climate change and by improved farm management, illustrating that disaggregated impact assessments are needed to effectively inform decision making towards climate change adaptation

Using AgMIP Regional Integrated Assessment Methods to Evaluate Vulnerability, Resilience and Adaptive Capacity for Climate Smart Agricultural Systems

The predicted effects of climate change call for a multi-dimensional method to assess the performance of various agricultural systems across economic, environmental and social dimensions. Climate smart agriculture (CSA) recognizes that the three goals of climate adaptation, mitigation and resilience must be integrated into the framework of a sustainable agricultural system. However, current methods to determine a systems’ ability to achieve CSA goals are lacking. This paper presents a new simulation-based method based on the Regional Integrated Assessment (RIA) methods developed by the Agricultural Model Inter-comparison and Improvement Project (AgMIP) for climate impact assessment. This method combines available data, field- and stakeholder-based surveys, biophysical and economic models, and future climate and socio-economic scenarios. It features an integrated farm and household approach and accounts for heterogeneity across biophysical and socioeconomic variables as well as temporal variability of climate indicators. This method allows for assessment of the technologies and practices of an agricultural system to achieve the three goals of CSA. The case study of a mixed crop livestock system in western Zimbabwe is highlighted as a typical smallholder agricultural systems in Africa

Sustainable intensification of smallholder farming in central Mozambique: Benefits from better integration of crops and livestock

The Government of Mozambique gives particular importance to strategies for sustainable intensification of agriculture in the smallholder-farming sector, accounting for more than 95% of the total agricultural land. Better integration of crops and livestock is key to sustaining vital smallholder farming, rewarding higher agricultural production and improving the overall wellbeing of smallholder farms, especially in provinces like Tete and Manica, with high potential for crops and livestock. Farmers with animal draft power can cultivate larger parts of their land in time and are thereby able to also produce more feed, critical for improving animal performance. Better-managed and fed animals reproduce more, provide better draft services and avail manure as important source of locally available organic fertilizer. Farmers thereby increase production at reduced costs and risk, overall farm net returns increase more than through single technologies. These benefits can be harvested over large areas, and with different agro-ecological potential. Farmers with cattle cultivated more land than those without cattle: in Dororo, Manica province, with high agro-ecological potential, 4.4 ha as compared to 2.9 ha cropland; in drought prone Marara, Tete province, 3.1 ha of as compared to 2.1 ha. On average farmers with cattle made 20% higher cereal yields in Dororo, and 30% higher cereal yields in Marara. Yet 52% and 45 % of the households don’t have cattle in Dororo and Marara respectively. This leaflet illustrates the benefits from better integration of crops and livestock. We describe forage production and draft power animal management as two complementary technologies critical for sustainable intensification of smallholder farms, demonstrated in the MOREP project. These technologies are useful for farmers in similar environments like in Tete and Manica provinces

Evaluation of water productivity, stover feed quality and farmers' preferences on sweet sorghum cultivar types in the semi-arid regions of Zimbabwe

Summary Twenty sweet sorghum cultivars that included 17 improved cultivars (experimental grain, forage, dual and India released varieties) from India and 3 landraces from southern Africa were evaluated for their use as an alternative food and fodder crop for crop-livestock farmers. The trials were conducted during 2007/08 season in semi-arid conditions at Matopos Research Station, Zimbabwe. Three methods of assessment were applied to help identify suitable cultivars: grain and stover water productivity (WP), stover feed quality traits and farmers' assessment of cultivars in the field. Grain and stover WP ranged from 0.6 to 2.7 kg m -3 and 1.2 to 4.0 kg m -3 respectively. We observed significant differences in cultivar groups on plant height, time to maturity, harvest index, grain WP, nitrogen uptake, nitrogen harvest index and stover metabolizable energy and digestibility (P <0.001), and sugar (Brix %) and stover WP (P <0.05). In the improved grain and dual type cultivars, grain yield increased by 118% compared to landraces and by 69% over the forage type while in the India released variety type cultivars grain yield increased by 86% compared to landrace yields and by 44% over the forage cultivars with an increase in stover yield. The landrace type was superior to all sweet sorghum types on feed quality traits (metabolizable energy and digestibility). The farmers' assessment demonstrated the need to combine qualitative and quantitative screening methods. The farmers' combined analysis showed that forage and grain yield are important parameters to the farmers following crop-livestock production systems. Results of the three methods showed that the dual type SP1411 was the preferred cultivar. Future breeding activities should therefore be directed towards the tradeoff between grain yield potential and stover feed quality in the quest for developing a wider range of dual purpose cultivars

Closing the yield gap of soybean (Glycine max (L.) Merril) in southern Africa: a case of Malawi, Zambia, and Mozambique.

Open Access JournalIntroduction: Smallholder farmers in Sub-Saharan Africa (SSA) are increasingly producing soybean for food, feed, cash, and soil fertility improvement. Yet, the difference between the smallholder farmers’ yield and either the attainable in research fields or the potential from crop models is wide. Reasons for the yield gap include low to nonapplication of appropriate fertilizers and inoculants, late planting, low plant populations, recycling seeds, etc. Methods: Here, we reviewed the literature on the yield gap and the technologies for narrowing it and modelled yields through the right sowing dates and suitable high-yielding varieties in APSIM. Results and Discussion: Results highlighted that between 2010 and 2020 in SSA, soybean production increased; however, it was through an expansion in the cropped area rather than a yield increase per hectare. Also, the actual smallholder farmers’ yield was 3.8, 2.2, and 2.3 times lower than the attainable yield in Malawi, Zambia, and Mozambique, respectively. Through inoculants, soybean yield increased by 23.8%. Coupling this with either 40 kg ha−1 of P or 60 kg ha−1 of K boosted the yields by 89.1% and 26.0%, respectively. Overall, application of 21–30 kg ha-1 of P to soybean in SSA could increase yields by about 48.2%. Furthermore, sowing at the right time increased soybean yield by 300%. Although these technologies enhance soybean yields, they are not fully embraced by smallholder farmers. Hence, refining and bundling them in a digital advisory tool will enhance the availability of the correct information to smallholder farmers at the right time and improve soybean yields per unit area

Evaluation of water productivity, stover feed quality and farmers’ preferences on sweet sorghum cultivar types in the semi-arid regions of Zimbabwe

Twenty sweet sorghum cultivars that included 17 improved cultivars (experimental grain, forage, dual and India released varieties) from India and 3 landraces from southern Africa were evaluated for their use as an alternative food and fodder crop for crop-livestock farmers. The trials were conducted during 2007/08 season in semi-arid conditions at Matopos Research Station, Zimbabwe. Three methods of assessment were applied to help identify suitable cultivars: grain and stover water productivity (WP), stover feed quality traits and farmers’ assessment of cultivars in the field. Grain and stover WP ranged from 0.6 to 2.7 kg m-3 and 1.2 to 4.0 kg m-3 respectively. We observed significant differences in cultivar groups on plant height, time to maturity, harvest index, grain WP, nitrogen uptake, nitrogen harvest index and stover metabolizable energy and digestibility (P <0.001), and sugar (Brix %) and stover WP (P <0.05). In the improved grain and dual type cultivars, grain yield increased by 118% compared to landraces and by 69% over the forage type while in the India released variety type cultivars grain yield increased by 86% compared to landrace yields and by 44% over the forage cultivars with an increase in stover yield. The landrace type was superior to all sweet sorghum types on feed quality traits (metabolizable energy and digestibility). The farmers’ assessment demonstrated the need to combine qualitative and quantitative screening methods. The farmers’ combined analysis showed that forage and grain yield are important parameters to the farmers following crop-livestock production systems. Results of the three methods showed that the dual type SP1411 was the preferred cultivar. Future breeding activities should therefore be directed towards the tradeoff trade off between grain yield potential and stover feed quality in the quest for developing a wider range of dual purpose cultivars