A comprehensive evaluation of wheat/maize agronomic water-saving modes in the piedmont plain region of the Mount Taihang

Saving water in wheat/maize cultivation is critical not only for preventing over-exploitation of groundwater, but also averting devastating water crisis in the piedmont plain of the Mount Taihang. At the studied area, former researchers had established a series of wheat/maize agronomic water-saving techniques, such as water-saving cultivars introduction, wheat/maize straw mulching, regulated deficit irrigation, optimization of growing stage and plant spacing. Four integrated wheat/maize agronomic water-saving modes were established based on these existing techniques. They were conventional mode (with 3 irrigations before sowing, and at jointing and flowering stages of wheat and maize), integrated water-saving mode (with 2 irrigations at jointing and flowering stages of wheat and maize), mode A (with 1 irrigation at jointing stage of wheat and maize) and mode B ( with 1 irrigation before sowing). The modes were comprehensively evaluated with entropy weight method in relation to wheat/maize production efficiency, economic/ecological benefits and water-saving efficiency. Based on the study, the order of efficiency of four tested wheat/maize irrigation modes was as follows: integrated water-saving mode > mode A > mode B > conventional mode (control). The optimal wheat/corn water-saving mode was therefore the integrated water-saving mode. It had the lowest fertilizer input, and highest input-output ratio, net revenue, water use efficiency and economic water use efficiency. Saving water in wheat/maize production is the direction of future development. Farmers’ awareness of agricultural water-saving should be strengthened, integrated water-saving mode should be promoted in wheat/maize farming in the piedmont plains of the Mount Taihang.