Axe 3: Production stability and crop diversification

Assessing the production stability in a context of adverse climate and of crop diversification (Axe 3)

Participants : C Barbu, C Colnenne, T Doré, A Gauffreteau, N Guilpart, D Makowski

In Axe 3, we address the following questions:

(i) Does climate change induce higher yield instability?

(ii) It is possible to reduce production instability by a crop diversification?

(iii) How climate change will impact cropping zones?

A first challenge concerns the assessment of climate impact on crop yields. A large number of public and private institutions have developed weather-based and satellite-based indices to anticipate yield losses. In addition to these simple indices, a flurry of aggregated indices based on statistical methods, machine learning techniques, and process-based models have been produced, and little is known about their effectiveness to actually anticipate yield loss. It is becoming urgent to conduct an in-depth evaluation of their accuracy and to determine their ability to analyze risk of yield loss under contrasted climate change scenarios and under several diseases or pests’ attack, potentially increased with climate change.

A second challenge concerns the evaluation of the capacity of crop diversification to mitigate production instability. Monocultures and the intensive use of synthetic inputs are often seen as factors increasing vulnerability of cropping systems to climate change. It has been hypothesized that a diversification of the agroecosystems (longer crop sequences, mixing of species and varieties etc.) will reduced adverse climate change impacts. But the ability of crop diversification to reduce the vulnerability to climate change has not been clearly demonstrated.

Finally, there are now evidences that climate change will have an impact on the distribution area of crops in the next coming decades. Although several agricultural regions are threatened by climate change, the warmer climate expected in high latitude regions may offer new opportunities for agriculture expansion in the north. It is important to explore potential distributions of cropping areas for informing major stakeholders on benefits or disadvantages of alternative land use scenarios, in particular scenarios based on diversified cropping systems. Therefore, the key question is not only “how to crop” but, also, “where to crop".