Just the right amount of efficiency

This post is part of the Agriculture and Ecosystems Blog’s month-long series on Resilience.

We know, scientific progress can be frustratingly slow, and research at the boundary of science and policy-making can be even slower. However, I felt a sense of dismay when I read this paragraph in the summary of the 2005 Millennium Ecosystem Assessment (MEA):

"If the consumption of natural capital had grown as quickly as the global economy, Earth’s systems would be in a very much worse state than they are at present. In fact, important improvements in efficiency have been introduced, such as less energy-intensive products and processes or farming techniques that use less water and create less pollution. Unfortunately, these efficiencies are outweighed by the fact that more people are consuming ever-greater quantities of goods and services, so the total toll on natural systems continues to grow. This is not a matter of rising population alone, but also of lifestyle changes among those enjoying greater prosperity.”

Photo: Anna-Marie Ball/IFPRI

It is the clarity of the statement that gets me. Consider for a moment the wealth of knowledge that went into the MEA; it is obvious that the main challenges confronting food security and environmental protection had been identified well over a decade ago. Since then a lot of effort has been put into better defining the magnitude of the threats, but what about solutions?

Are we closer to implementing workable options to control degradation of ecosystem services, the high rates of biodiversity loss, and counteracting a state of things where “efficiencies are outweighed by the fact that more people are consuming ever-greater quantities of goods and services, so the total toll on natural systems continues to grow”?

Double efficiency: produce more with fewer externalities

In order to sustainably feed a growing population, agriculture must do better to protect its natural resource base. At least in part, sustainable agricultural intensification is about a double efficiency: producing more output per unit of input, and producing fewer externalities (e.g. nutrient leaching, greenhouse gas emissions, land use) per unit of output. There is little doubt that technological advancement can bring about additional improvements in efficiency and environmental protection but how much is enough? I think the question remains to be answered.

In February 2014, IFPRI completed a study which uses a combination of crop and economic models to explore the potential of several agricultural technologies and practices to enhance productivity of maize, rice and wheat across all regions of the world under climate change conditions. The chosen technologies and practices are some of the most promising for building soil fertility, making more efficient use of resources, having a lesser impact on the environment and improving the overall resilience of agriculture production to climate change. The list of improved technologies and practices includes precision agriculture, drought tolerant and nitrogen use efficient crop varieties, minimum tillage, water harvesting, and integrated soil fertility management among others.

Results show that nitrogen use efficiency, minimum tillage and heat tolerant crop varieties have the largest overall potential to improve yields in 2050 compared to a business as usual scenario. Nitrogen use efficiency, minimum tillage and integrated soil fertility management also substantially increase the productivity of nitrogen inputs, thus lowering nitrogen leaching into the soil.

Moreover, improved productivity reduces the amount of land necessary for production. In 2050, heat tolerant varieties could lower the need for maize harvested area by 8 percent, nitrogen use efficiency could lower it by 7 percent for rice, and minimum tillage by 7 percent for wheat.

Are these gains in efficiency good enough?

These increased efficiencies are welcome. These technologies promise to reduce pressure both on the ecosystem matrix surrounding farmland, and on downstream ecosystems, therefore contributing to more resilient landscapes.

However, the initial questions still remain. Are these gains in efficiency good enough? Do these reductions in land-use significantly help to reduce loss of biodiversity and ecosystem services? And can we afford a scenario that still entails further losses of land despite improvements in yields?

If we look back at the MEA, the answer is probably no; such a scenario is not safe. But technologies are not the only weapon in our arsenal, and for better or for worse we don’t have the luxury of betting on a single solution.

Reducing food waste, controlling consumption of resource-intensive commodities and improving allocation of food through trade must all be part of the overall strategy for sustainable food security. These options will all contribute to reducing the demands on food systems and the need for intensification, thereby lowering the risks of continuing impacts on the environment.

Because the degree of success of all these options is still uncertain, we need to invest aggressively in all of them. Yet, financial resources are finite. Therefore, we need clear targets if we are to succeed. We need to know how much efficiency gain is enough to significantly lower environmental damage. What could the target be, and is it economically feasible, when combined with scenarios of potential waste reduction and consumption control?

Work on the impact of technology adoption and scenario analysis of energy use and dietary changes by IFPRI, as well as the scenario analysis recently performed by Tilman and colleagues exploring environmental impacts of meeting increased crop demand, provide us with some of the tools to start answering these critical questions.