3. Productivity Growth and Yields in the Global Crops Sector

Despite strong growth in population and incomes over the past century, cropland expansion has been modest and crop prices have trended downwards. This remarkable accomplishment has been largely due to technological innovation as well as intensification of crop production. This chapter explores the topic of crop productivity growth and its implications for long term land use, the environment and food security. It begins with a review of the historical evidence before moving into the debate about future productivity growth. Here, there are two distinct ‘camps’: one focusing on slowing yield growth to paint a relatively pessimistic picture, and one focusing on strong growth in total factor productivity (TFP) in order to find grounds for optimism in feeding the world in 2050. We find grounds for reconciling these two points of view when we draw a distinction between different measures of productivity growth. We also discuss one of the key determinants of future productivity growth—namely investment in research and development of new crop varieties and technologies for cultivation. To conclude the chapter, we present a series of simulations to 2050 using the SIMPLE model. These serve to highlight the fact that yields and productivity growth are not synonymous in an economic model. Rather, output per hectare depends both on TFP growth as well as the intensification of production.