# Agriculture 4.0: Is Sub-Saharan Africa Ready?
## 2 Prospects and Challenges for Agriculture 4.0 Adoption in Sub-Saharan Africa
### Scale  
Smallholders continue to dominate agriculture in SSA, with 80% of agricultural output produced by farmers with landholdings less than 2 hectares on average, [27]. Some scholars have suggested that improvements in agricultural productivity in SSA, just like in the case of the Asian Green Revolution, are likely to be driven by smallholders who currently control most of the landholdings [44]. Others have argued that relying on the conventional smallholder model of agriculture is inefficient because African smallholder productivity is very low, e.g., [20; 45]. Either way, understanding the scale at which agriculture 4.0 technologies are likely to operate is particularly important for SSA; and the reality is that, at least in the short to medium term, smallholder farmers will remain important in the sector. Agriculture 4.0 has often been associated with large-scale farming [13; 46]. For example, unmanned aerial vehicles (UAVs) are increasingly being used for fertilisers and chemical spraying. UAVs, in combination with smartphone platforms to provide remote sensing data, also use global positioning systems (GPS) for digital soil mapping [10; 11; 14; 15] for various environmental and agricultural development purposes [47]. However, uptake of this technology was reported in a South African study to be low [47]. Modalities already exist in SSA where smallholder farmers could rent these or similar services or jointly source such \"lumpy\" technologies, thereby overcoming any \"scale\" constraint. For example, in recent years, SSA countries have seen elements of the 'fourth agricultural revolution' technology such as the mobile application for tractor hiring being promoted by international organisations including the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) and the private sector [12]. One specific example is a blockchain-enabled application that links tractor providers and smallholder farmers to promote agricultural mechanisation [48]. This application, called Hello Tractor, is a software that provides a platform for renting tractors for land cultivation from owners by smallholders. More broadly, ICRISAT's innovation Hub (iHub) has been developed to support activities along the crop production value chains from seed certification, product manufacturing and retail [49], many of which are scale neutral and as such could be of direct benefit to smallholder farmers in SSA. Agriculture 4.0 technologies could have an important role in African countries where fertiliser use has long been low [50], despite many initiatives to increase its use. For example, in June 2006, the African Union (AU) member states' Ministers of agriculture, at a summit in Abuja, Nigeria, resolved to increase the level of fertiliser use from 8 to 50 kg per hectare on average by the year 2015. This was despite a lack of scientific evidence to support the value of such an arbitrary increase [51], prompting concerns that the move would likely be counterproductive, leading to an increased cost of production. Agriculture 4.0 technologies such as soil mapping for soil analysis could offer more sustainable alternativesby identifying areas of nutrient deficiencies to inform precision fertiliser application that is cost-efficient and environmentally sound [14]. Remote sensing data has long been used in agriculture, whether to simply map cropland, or to determine biomass, yields, and crop stress [52]. Further, it is becoming more affordable, in part due to the availability of free high-resolution satellite imagery. Digital soil mapping has the potential to identify the location of high-value agricultural land by providing detailed information on soils and is already being used in SSA [47]. However, the scale and heterogeneity of Africa's agricultural landscapes are likely to continue to pose challenges, particularly for smallholder farmers [43]. For example, [PERSON], [PERSON] [27] highlight, in particular, the difficulty of using satellite data to determine crop yields in smaller farms.