Ecological water requirement of plant–soil systems along the Silk Road Economic Belt: A case study of the Guanzhong–Tianshui region, China.

“The Belt and Road” refers to the Silk Road Economic Belt and the 21st‐Century Maritime Silk Road. In this paper, the Guanzhong–Tianshui region is selected as a case study, which is located at the starting point of the Silk Road Economic Belt. First, the spatial distribution maps of plant and soil types are obtained based on the TM remote sensing images and the soil texture data. The boundaries of the third‐level watershed are extracted based on the digital elevation model data. Then the corresponding mathematical models are used to evaluate the ecological water requirements of the plant–soil systems. Also, the spatial distribution characteristics are analysed at the landscape scale and the third‐level watershed scale. The results show that the spatial differences of ecological water requirement in the Guanzhong–Tianshui are obvious. At the plant–soil landscape scale, the ecological water requirement per unit area of the woodland‐clay loam is the highest, about 0.4777 m3/m2, while that of the grassland‐gravel loam is the lowest, about 0.2813 m3/m2. At the third‐level watershed scale, the ecological water requirement per unit area in the Weihe watershed (Jinghezhangjiashan above) is the highest, about 0.4123 m3/m2, while that in the Weihe watershed (Longmen to Sanmenxia) is the lowest, about 0.3002 m3/m2. The study offers scientific references for the regional ecological environment protection and ecosystem management. [ABSTRACT FROM AUTHOR]