Yield Stability and Resilience: Looking for Signals in Long-Term Data.

Climate change and crop production models predict significant changes in interannual variability of crop yields as average annual temperatures increase and rainfall patterns become more erratic. Identifying cropping systems that are more resilient to these types of changes will be key to adaptation. Here we present the results of an analysis using data from 3 long-term cropping systems experiments. Across all three experiments, treatments designed to increase soil organic matter, either through direct organic matter inputs or increased rotational diversity, were most effective at reducing interannual variability and decreasing the likelihood of poor production in bad weather years. These results are consistent with other experimental results suggesting that soil organic matter improves the buffering capacity of agricultural systems by increasing water retention of soils, thereby reducing physiological stress from evapotranspiration. Focusing on management strategies that improve soil organic matter stocks, elaborating mechanisms by which carbon is stabilized in soils, and developing targets for different agricultural systems could be key in improving the resilience of agricultural systems in the face of climate change.