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Soil carbon dioxide (CO2) fluxes are a critical component in understanding carbon sequestration. In sub-Saharan Africa, empirically measured CO2 emissions data from diverse land-use systems is limited. Soil CO2 emission rates were measured in the Limpopo Province, South Africa for 12 months at two-week intervals in natural systems (forest and shrubland) and commercially managed orchards (avocado and citrus) to establish seasonal dynamics of soil CO2 emissions across these land-use systems. The results showed a variation in emission rates with the variation depending on the season. In the spring and winter, soil CO2 emission rates in citrus were four times higher than in the shrubland due to higher moisture levels. However, in the summer season, the forest emission rates were 40% higher than in citrus due to higher soil organic carbon content. Organic carbon stocks were higher in the forest (1.19 kg/m2) compared to the other land uses. This study revealed differences in soil CO2 emission rates among land-use systems, with the cumulative amount of CO2 emitted over a 12-month period following the order: forest (39.3 tons/ha) > citrus (36.1 tons/ha) > shrubland (28.1 tons/ha) > avocado (26.9 tons/ha). Thus, understanding the emission patterns from various ecosystems can inform strategies for mitigating greenhouse gas emissions. [ABSTRACT FROM AUTHOR]

Smallholder farmers in rural communities that are prevalent in provinces such as Limpopo are not only confronted with the challenges of their direct environment but they also face new challenges in terms of the type of crops to produce in the era of climate change and variability. These challenges influence the way farmers make key decisions. Given that agricultural practices affect more than the farming unit, it is of interest to understand farmers’ behaviour. A survey was carried out across agroecological zones in Limpopo. Six hundred farmers were interviewed to establish key factors underlying their choice of oilseeds to produce. Descriptive statistics and factor analysis were used to analyse the data. Results showed that the choice of crops to produce was influenced by socioeconomic and climatic factors. Factor analysis indicated that floods were the most influential factor in the choice of oilseeds. This was followed by implements, temperature, rainfall, cash, irrigation equipment, input availability and food security. Determining factors varied amongst farmers producing groundnut, soybean and sunflower. Farmers were more hesitant to cultivate sunflower and soybean primarily because of the lack of familiarity with these crops and this in turn magnified the risk created by the uncertainty surrounding the future financial returns from these crops. Further results highlight concerns about resource and input availability in the area. The provision of support in terms of inputs availability, implements, the development of reliable networks for information dissemination and training of oilseed farmers beyond their local environment and sphere is critical. This is particularly so given there is a host of site-specific factors that have a bearing on the farmers’ decision-making processes. Stakeholders therefore need to take into account the variation in factors influencing farmers’ decisions, and put in place site specific measures to properly guide farm management choices.