Sustainable intensification of agriculture amidst yield stagnation: Journal Club with Monica Ortiz

For this week’s Journal Club, Grantham Scholar Monica Ortiz introduced the concept of ‘sustainable intensification’. In this post, she explains how this might be put into practice to help feed a growing population.

This week’s paper

Recent patterns of crop yield growth and stagnation‘ by D. K. Ray, N. Ramankutty, N. D. Mueller, P. C. West and J. A. Foley

monica-ortiz

As a first year PhD student, much of my time is spent reading scientific literature to gain a better understanding on food security and agriculture. A common message across many food security papers is that continuing business as usual is not an option if we are to feed our growing population: we need to intensify our agriculture, albeit in a way that does not cause further harm to our environment and its resources. This concept is called sustainable intensification, and it has been adopted by many agencies, including the United Nations Food and Agriculture Organisation.

However, what does sustainably intensified agriculture look like?

The report on the workshop proceedings of ‘Sustainable intensification in agriculture’ by the Food Climate Research Network (FCRN) and University of Oxford states that it is still not clear what sustainable intensification will look like on the ground. The report also notes that given different demand trajectories, trade-offs will inevitably arise and will need to be balanced. Clearly, agriculture that is intensified to meet our present and future needs may differ amongst production systems and in different places.

It is with this in mind that I picked the article ‘Recent patterns of crop yield growth and stagnation’ (Ray et al., 2012) to discuss at our weekly Journal Club. The article states that overall, historically, yields have improved in most crop production areas. However, in the most recent decades (1985-2005), global crop production increased by only 28% based on 2.5 million census observations from using high-resolution geospatial databases.

In addition, yields have either never improved, are stagnating, or have collapsed in about a third (24-39%) of areas planted with maize, rice, wheat and soybeans, which are the four most important crops for human consumption.

rice-mo
Rice, food for billions. Photo by Monica Ortiz.

Yield gains fall short of expected demands, and the patterns of recent yield stagnation and even collapse underscore the questions: Which crops and which geographic regions offer the best hope of meeting projected demands? Where should we be doing sustainable intensification in the first place?

I posed these questions to my colleagues with a hypothetical scenario that we were providing scientific advice to potential research funders to fund agricultural intensification and research in areas where a) yields are still improving, b) yields are stagnating (they peaked then plateaued), c) yields are declining, or d) yields have never improved. The caveat was they could only support one of the choices. This led to quite a lively and active discussion which brought some interesting perspectives.

Some of the Scholars found it interesting how there are areas in the world that still have not experienced any improvement in yields since the 1960s. Areas where yields never improved might be severely limited by their biophysical capacity to support agriculture in the first place, in addition to reasons connected to the political climate of areas, which may have interfered with stable production. Investing in areas where yields were still increasing could mean that there is some assurance of good yields, because this means that there is a ‘track record’ for good production.

Others said that they would support investment and research in areas where yields collapsed, because supporting agriculture there could bring more stability of food production precisely where it is needed. However, many Scholars also felt that areas where yields were stagnating meant that these areas would already have the resources, infrastructure and potential to have high yields.

While we did not reach a firm consensus (although there was a lean towards stagnating yields), we did agree with the paper’s conclusion that considerable investment in agriculture is needed in the coming decades to meet the growing demand for food while simultaneously maintaining a liveable environment. The FCRN-Oxford conclude with an important statement that is particularly important in this discussion towards intensifying agriculture: sustainable intensification as a concept should be decoupled from production targets. As scholars shared and as our food waste and food poverty seminar will tackle, we do produce enough food and in fact waste a lot of it. Sustainable intensification should be about optimising productivity instead of production.

So instead perhaps, the question should be: where should we not be doing sustainable intensification?

References

Recent patterns of crop yield growth and stagnation‘. (2012). Nature Communications

Garnett T and Godfray C (2012). Sustainable intensification in agriculture: Navigating a course through competing food system priorities, Food Climate Research Network and the Oxford Martin Programme on the Future of Food, University of Oxford, UK