Climate change in different geographical units and its impact on land production potential: a case study of Shaanxi Province, China

Land production potential (LPP) was the maximum grain yield in one year that can be produced by land under the limitations of climate conditions and in the absence of pests and diseases and other factors. Whether climate change was increasing or reducing the LPP in a given region was uncertain. Therefore, Shaanxi Province was selected to analyze the regional differences in climate change and its effects on LPP change and to identify the main climatic factor restricting LPP in different regions by combining Global Agro-Ecological Zone (GAEZ) model with the Geodetector model. Results showed that the temperature in Shaanxi Province showed an upward trend in 2000-2015; the rise in temperature to the north of Qinling Mountain (QM) was less than that to the south of QM. However, rising temperature had a yield-improving effect to the north of QM and a yield-decreasing effect to the south of QM. There was a precipitation increase in Arid Sandy (AS) area and Loess Plateau (LP), and the precipitation reduced in all other geographical units. The increase in LPP of Shaanxi mostly was caused by increasing precipitation. However, precipitation was declined and reduced LPP to the south of QM; that is, precipitation decline was the dominated climatic factor for LPP decrease in QM, Hanjiang Basin (HB), and Daba Mountain (DM). To the north of QM, LPP in AS, LP, and Guanzhong Plain (GP) both dramatically increased, mainly improved by rising temperature, increasing precipitation, and rising temperature, respectively.