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[Objective] Shaanxi Province is an important grain, oil, and fruit production base in China, but most part of the province is located in the semi-arid zone. Limited water resources are the biggest constraint to the sustainable development of local economy and society. Quantitative evaluation of water consumption and water-saving potentials in crop production is crucial for water resource-adapted agricultural development and green and high-efficiency water-saving. [Methods] Based on the spatiotemporal evolution characteristics of the annual blue water footprint (irrigation water consumption) and green water footprint (effective precipitation consumption) of growing 10 major crops under irrigated and rainfed conditions in Shaanxi Province from 1989 to 2019, the engineering water-saving potential and real water-saving potential of crop production in typical years were deduced. [Results] The results show that: (1) The consumptive water footprint per yield of all crops in Shaanxi Province showed an overall downward trend in the 30-year study period, and the water footprint of individual crops had visible differences between cities. The provincial average unit consumptive water footprint of apple production decreased by 91.3%; the difference of consumptive water footprint of wheat production between cities reached 3.41 m3/kg. At the same time, the grey water footprint of apple and rapeseed production showed an increasing trend. (2) The total consumptive water footprint of crop production was 16.055 billion m3/a in 2019, slightly decreased by 1.8% from 1989. Corn, wheat, and apple production contributed more than 80% of the total consumptive water footprint of provincial crop production. (3) The water-saving potential, blue water saving potential, and green water saving potential of crop production in Shaanxi Province were 62%, 68%, and 49%, respectively. [Conclusion] There is a great potential of agricultural water-saving in Shaanxi Province. There are two preliminary suggestions: (1) Combining technology and management measures to accelerate agricultural water-saving and efficiency; (2) Accelerate scientific and accurate fertilization to reduce environmental pressure.

Evapotranspiration over crop growth period, also referred to as the consumptive water footprint of crop production (WFCP), is an essential component of the hydrological cycle. However, the existing high-resolution consumptive WFCP datasets do not distinguish between soil evaporation and crop transpiration and disregard the impacts of different irrigation practices. This restricts the practical implementation of existing WFCP datasets for precise crop water productivity assessments, agricultural water-saving evaluations, the development of sustainable irrigation techniques, cropping structure optimization, and crop-related interregional virtual water trade analysis. This study establishes a 5-arcmin gridded dataset of monthly green and blue WFCP, evaporation, transpiration, and associated unit WFCP benchmarks for 21 crops grown in China during 2000–2018. The data simulation was based on calibrated AquaCrop modelling under furrow-, sprinkler-, and micro-irrigated as well as rainfed conditions. Data quality was validated by comparing the current results with multiple public datasets and remote sensing products. The improved gridded WFCP dataset is available at 10.5281/zenodo.7756013 (Wang et al., 2023) and effectively compensated for the gaps in the existing datasets through (i) revealing the intensity, structure, and spatiotemporal evolution of both productive and non-productive blue and green water consumption on a monthly scale, and (ii) including crop-by-crop unit WFCP benchmarks according to climatic zones. [ABSTRACT FROM AUTHOR]