Chapter 15 - Do Crop Rotations Improve the Adaptation of Agricultural Systems to Climate Change? A Modeling Approach to Predict the Effect of Durum Wheat-Based Rotations on Soil Organic Carbon and Nitrogen

Abstract

Mediterranean rainfed cropping systems, mostly based on durum wheat (DW) monocropping for semolina production or in succession with bare fallow (BF), could be highly responsive to climate change. We aimed to assess DW-based systems and their adaptation to climate change in terms of yields, soil organic carbon (SOC) sequestration, and greenhouse gas (GHG) emissions by using the EPIC model based on experimental data. The rotations were CDW (continuous DW), DW-BF, DW-DW (2×DW)-BF, DW-CP (chick pea), 2×DW-CP, 2×DW-TB (thick bean cover crop), 4×DW-TB. The current and future climate change scenarios were obtained by three general circulation models (GCMs) showing different rainfall and temperatures changes. GCMs were derived from the AGRI4CAST Resources Portal managed by the Joint Research Centre and represent a period of 30 years centered in 2000 and in 2030, with the A1B emission scenario. Yields under climate change were mostly influenced by rainfall, and the best performing rotations were DW-CP or 2×DW-CP. No rotations were able to sequester SOC, but losses were reduced in DW-BF and in the rotations including CP. CO2 emissions slightly increased by climate change. N2O emissions were negligible (<0.1kgha−1 in 30 years).