Adapting Towards Climate Change: A Bioeconomic Analysis of Winterwheat and Grain Maize

Abstract

Climate change (CC) will alter the environmental conditions for crop growth. In order to minimize negative CC impacts on cropping systems, farmers will have to adapt their management schemes. In this paper we analyzed CC impacts and adaptation in winterwheat and grain maize production using a bio-economic modeling approach in two study regions of the Swiss Plateau, which differed in their climate and soil types. Considered adaptation options reflected the adjustment of farmers’ management decisions with regard to nitrogen and irrigation strategies. To this end, we integrated the process-based crop growth model CropSyst into an economic decision model that accounted not only for the profit margin but also for production risks and thus reflected a risk-averse farmer’s management decisions at field scale. Since the relations between a farmer’s utility and his management decisions in cropping systems are nonlinear and highly complex we used genetic algorithms (GAs) as optimization technique. By doing so, we optimized the farmer’s certainty equivalent (CE) at field scale under different climate scenarios. Our results showed that CC will foster the use of irrigation as management option in grain maize production. For winterwheat, however, irrigation did not represent an optimal solution even under a CC scenario assuming decreases in monthly precipitation sums up to 30%. Furthermore, CC reduced for both crops the optimal nitrogen fertilization amount. Taking such adaptation responses in crop management into account, negative CC impacts on farmers’ utility could be partially mitigated.