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In this study, a factorial inexact copula stochastic programming (FICSP) method is developed for planning the regional-scale water-energy-food nexus (WEFN) system. The FICSP cannot only deal with uncertainties expressed as interval and random parameters, but also handle the interdependence among correlated random variables. Moreover, the multilevel factorial analysis embedded in FICSP is able to reflect the main and interactive effects among uncertain parameters. The IFCCP approach was then applied to planning the WEFN system for the City of Jinan, Shandong Province, China. A FICSP-WEFN model has been established under consideration of various restrictions related to water and land availability, food and vegetable demands and other environmental constraints. The obtained results indicated that the surface water and groundwater availabilities would be highly correlated with their marginals fitted through the Gaussian distribution and their dependence described by the Gaussian copula. Under limited water resources, the corn cultivation would be prioritized but the increase of water resources tends to increase the wheat cultivation and reduce corn planting. Under the advantageous conditions where sufficient water resources are available, the additional water resources tend to be allocated to wheat and vegetables whilst corn cultivation would not be changed. Moreover, the surface and recycled water would be first utilized for crop production, with the remaining water requirements satisfied by groundwater. The results from factorial analysis indicated that the system benefits would be increased under the demanding conditions through increasing the joint risk level and also the violation risk for surface water availability or decreasing the violation risk of groundwater availability. Nevertheless, the increase in the violation risks under the advantageous conditions would not necessarily lead to increased system benefit, implying that the crop cultivation patterns may be influenced by other restrictions rather than the water availability. In general, the developed FICSP method cannot only generate desired management strategies for WEFN system under consideration of joint risks, but also help track the factors that make dominant impacts on the WEFN management practices. • A FICSP approach is developed for water-energy-food nexus management. • The copula is adopted to quantify correlated variables in WEFN system. • Factorial analysis is used to reflect interactions among uncertain parameters. • Results can support the management of WEFN system under different risk levels. [ABSTRACT FROM AUTHOR]

Climate change impacts crop productivity as atmospheric conditions and water supply change, particularly in intensive cropping areas. This study used the validated AquaCrop Model, which was run with downscaled daily climate data produced by SDSM and CanESM2. The changes in the potential grain yield of winter wheat and summer maize and water budget during the cropping seasons were estimated for the Huang-Huai-Hai Plain (3H Plain) under RCP4.5 and RCP8.5 scenarios. The results show that the potential yield of winter wheat is increasing with similar spatial patterns in the 2030s, 2050s, and 2080s, with much of the increase is distributed in Shandong and northeastern parts of Henan. During the winter wheat growth period, the water budget deficit will likely improve from −210 mm in the 2030s to −202 mm in 2080s under RCP4.5 and from −206 mm in the 2030s to −191 mm in 2080s under RCP8.5 across the 3H Plain. The water budget during the winter wheat period will continue to be in deficit in the north 3H Plain and improvements are estimated mostly in the lower southern areas of the Plain. The summer maize potential yield is estimated to increase from the baseline period, but yields will decrease by 0.81%, 1.19%, and 2.10% in the 2030s, 2050s, and 2080s, respectively, under RCP8.5 compared to RCP4.5. During the summer maize growth period, the water budget is also estimated to improve from 109 mm in 2030s to 126 mm in 2080s under RCP4.5 and 107 mm in the 2030s to 163 mm in 2080s under RCP8.5. This increase is mainly estimated in the central and south of the 3H Plain. The estimated ET c of winter wheat shows no significant decrease, while the reduction of 6 mm and 13 mm for summer maize is observed under RCP4.5 and RCP8.5, respectively. The study provides scientific evidence to devise adaptation and mitigation climate change strategies for agricultural productivity and water resource management. • The potential winter wheat yield will increase under RCP4.5 and RCP8.5 scenarios. • The increase in wheat yield follows a similar spatial pattern under both RCP scenarios. • The potential summer maize yield will decrease under RCP8.5 as compared to RCP4.5. • Water deficit for wheat will remain similar to the present with increased temperature. • Water budget during summer will significantly improve in the latter half of this century. [ABSTRACT FROM AUTHOR]