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

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

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

Economic trade-offs of biomass use in crop-livestock systems: Exploring more sustainable options in semi-arid Zimbabwe

In complex mixed crop-livestock systems with limited resources and biomass scarcity, crop residues play an important but increasingly contested role. This paper focuses on farming systems in the semi-arid areas of Zimbabwe, where biomass production is limited and farmers integrate crop and livestock activities. Conservation Agriculture (CA) is promoted to intensify crop production, emphasizing the retention of surface mulch with crop residues (CR). This paper quantifies the associated potential economic trade-offs and profitability of using residues for soil amendment or as livestock feed, and explores alternative biomass production options. We draw on household surveys, stakeholder feedback, crop, livestock and economic modeling tools. We use the Trade-Off Analysis Model for Multi Dimensional Impact Assessment (TOA-MD) to compare different CR use scenarios at community level and for different farm types: particularly the current base system (cattle grazing of maize residues) and sustainable intensification alternatives based on a CA option (mulching using maize residues ± inorganic fertilizer) and a maize–mucuna (Mucuna pruriens) rotation. Our results indicate that a maize–mucuna rotation can reduce trade-offs between CR uses for feed and mulch, providing locally available organic soil enhancement, supplementary feed and a potential source of income. Conservation Agriculture without fertilizer application and at non-subsidized fertilizer prices is not financially viable; whereas with subsidized fertilizer it can benefit half the farm population. The poverty effects of all considered alternative biomass options are however limited; they do not raise income sufficiently to lift farmers out of poverty. Further research is needed to establish the competitiveness of alternative biomass enhancing technologies and the socio-economic processes that can facilitate sustainable intensification of mixed crop-livestock systems, particularly in semi-arid environments