Virtual New Nitrogen, Phosphorus, Water Input, and Greenhouse Gas Emission Indicators for the Potatoes Consumed in China

Abstract

Based on China’s potato staple food policy, we chose potatoes as a study case to analyze the following indicators—the virtual new nitrogen factor (VNNF), the virtual new phosphorus factor (VNPF), the virtual irrigation-water (IW) factor (VIWF), the virtual total water (IW + precipitation) factor (VTWF), and the virtual greenhouse gas (GHG) emission factor (VCF) of the potatoes consumed by households in the six potato cultivation regions—by reviewing 220 publications from 2000 to 2020. The results showed that the VNNF ranged between 17.8 ± 7.8 and 30.1 ± 17.0 kg N kg−1 N in the consumed potato, the VNPF ranged between 8.4 ± 5.0 and 18.8 ± 11.3 kg P kg−1 P in the consumed potato, the VIWF ranged between 0.3 ± 1.0 and 1.8 ± 1.4 m3 IW kg−1 for the consumed standard yield (except in the three mainly rainfed potato regions), the VTWF ranged between 4.8 ± 2.2 and 9.3 ± 3.7 m3 total water kg−1 for the consumed standard yield, and the VCF ranged between 3.4 ± 1.5 and 5.9 ± 2.4 kg CO2 equivalent kg−1 for the consumed standard yield, under the conventional practice in the six potato cultivation regions. The normalization score results indicate that the northeast, northwest, southwest, and south of China are relatively more suitable regions in which to plant potatoes, based on the VNNF, VNPF, VIWF or VTWF, and VCF indicators.