Cropping intensity gaps: The potential for expanded global harvest areas

To feed the world’s growing population, more food needs to be produced. In addition to cropland expansion, which faces a variety of constraints, increasing cropping intensity may provide a promising means of boosting global crop production. Yet information on the size and location of cropping intensity gaps—the difference between the maximum cropping intensity that is theoretically possible and the cropping intensity that is realized today—for current global croplands, and how much additional production can potentially be achieved by closing these gaps, is lacking. To address this issue, this study proposes a spatial approach to exploring cropping intensity gaps around the year 2000. We identify these gaps by estimating the potential multiple cropping systems and actual multiple cropping systems for current global croplands and then calculating the difference. An adapted GAEZ (Global Agro-Ecological Zone) method was used to estimate potential multiple cropping systems on the basis of meteorological data, while actual multiple cropping systems were derived from satellite-based observations. The results show that global average cropping intensity gaps are 0.48 taking temperature constraints into account and 0.17 taking temperature and precipitation constraints into account. The Latin American region has the largest concentration of cropping intensity gaps under both scenarios, followed by Africa and Asia. We also find that most food-insecure countries in South Asia, Southeast Asia, and Africa south of the Sahara, as indicated by higher Global Hunger Index scores, have high or moderate cropping intensity gaps in both scenarios. Reducing the cropping intensity gaps would provide an opportunity to increase food production and help people escape extreme hunger. We estimate that global harvests on current croplands can be expanded by an amount equivalent to another 7.36 million and 2.71 million square kilometers (km2), respectively, under the temperature-limited and the temperature- and precipitation-limited scenarios. Latin America has the largest potential to achieve additional harvest area equivalents (more than 1.28 million km2) by closing cropping intensity gaps, followed by Asia (1.00 million km2). However, it must also be noted that although increasing cropping intensity can boost annual crop production per unit of cropland, this approach is not necessarily always appropriate, and the trade-offs between reducing cropping intensity gaps and caring for the environment must be considered. Only if cropping intensity can be increased sustainably is this a potential strategy for enabling global food production to meet rising food demands.