Sustainable intensification involves trade-offs between “sustainability” and “intensification”. Such trade-offs are likely to occur at the farm level given resource constraints and the timing of activities; some objectives are then prioritized over others. Assessing whether sustainable intensification (‘more output with less input’) is truly sustainable requires consideration of resource constraints and environmental and socio-economic performance at farm level.
The world faces an enormous challenge to supply affordable food to an ever-increasing human population without overexploitation of natural resources and degradation of ecosystems services. Sustainable intensification aims to narrow yield gaps on existing agricultural land while increasing resource-use efficiencies.
Progress towards sustainable intensification can be monitored by measuring system indicators such as crop yield and yield gap, resource-use efficiency and soil quality. Agronomic technologies that can deliver sustainable intensification at field level are in general available for the major cereal crops. At regional level, there is consensus that regions with large yield gaps can benefit most from sustainable intensification.
Yield gaps are defined as the difference between the potential (Yp) or the water-limited yield (Yw) and the actual yield (Ya) observed in farmers’ fields under irrigated or rainfed conditions, respectively. Decomposing yield gaps into efficiency, resource and technology yield gaps is helpful to identify the management drivers of existing yield gaps.
The efficiency yield gap is defined as the difference between the technically efficient yield (YTEx, the maximum yield that can be achieved for a given input level) and Ya and captures the contribution of sub-optimal time, form and/or space of crop management practices.
The resource yield gap is defined as the difference between the highest farmers’ yield (YHF) and YTEx and it is attributed to a sub-optimal amount of inputs applied. Finally, the technology yield gap is defined as the difference between Yp or Yw and YHF and it can be attributed to the use of inferior technologies (e.g., varieties or balanced nutrition) in farmers’ fields than those needed to reach Yp or Yw.
Sustainable intensification involves trade-offs between “sustainability” and “intensification”. Such trade-offs are likely to occur at the farm level given resource constraints and the timing of activities; some objectives are then prioritized over others.
Few studies have paid attention to this in the past. Hence it remains unclear how sustainable intensification of crops (at field level) works out at farm level, given constraints of land, labor, and capital availability and farmers’ decisions on resource allocation coupled with their prioritization of crop management activities.
Farmers’ decisions can be classified as strategic, tactical, and operational in terms of long, intermediate and immediate time scales. Their decisions determine actual resource-use efficiencies and the extent to which growth-defining, -limiting and -reducing factors are optimised for a specific crop in the biophysical environment of the farm. In turn, management decisions are strongly conditional on the socio-economic environment of the farm and the farmers’ personal priorities.
The analysis presented here draws upon a comparative analysis of farming systems with different degrees of agricultural development and intensification. This is important to capture low-, medium- and high-yielding systems with contrasting resource-use efficiencies and historical differences in yield progress.
We selected three contrasting farming systems for which suitable on-farm data at field and farm levels were available for yield gap decomposition. These farming systems were mixed crop-livestock systems in southern Ethiopia, specialised rice-based farming systems in Central Luzon (Philippines) and arable farming systems in the Netherlands. The farming systems exhibited different rates of yield progress and intensity of fertiliser use. They have also been influenced by different degrees of structural adjustment in the national economy over the past half-century.
Assessing whether sustainable intensification (‘more output with less input’) is truly sustainable requires consideration of resource constraints and environmental and socio-economic performance at farm level. We conclude that whilst there is large potential for intensification (‘more output with more input’) in southern Ethiopia, where yield gaps are about 80% of Yw, this is currently neither economically nor environmentally sustainable at farm level.
The same applies to rice farming in Central Luzon where the combination of negative profitability and a heavy reliance on hired labour slow the progress towards sustainable intensification as a way to improve NUE and increase rice yields beyond 50% of Yp.
Although high yields in the Netherlands, where yield gaps are only 20 – 30% of Yp, are associated with higher economic performance and resource-use efficiency, future research should investigate options for increasing resource-use efficiency and lowering environmental impacts through reducing input intensity (‘same output with less input’).
Yield gap closure in the Netherlands, and other intensive farming systems in Europe and the Americas, was largely accompanied by public investments encouraging the adoption of innovations and supporting agricultural markets (including, subsidies, price support and other institutional supports) which in turn made technologies accessible and affordable for farmers.
Agricultural transformation, including the adoption of sustainable intensification technologies, is thus only likely to take place where public investments to support farmers are ensured, even in regions with large yield gaps.
Read the study:
Silva JV, Reidsma P, Baudron F, Laborte AG, Giller KE, van Ittersum MK (2021) How sustainable is sustainable intensification? Assessing yield gaps at field and farm level across the globe. Global Food Security, Volume 30.
