Effects of Different Ecological Measures on Water Use Characteristics of Amorpha fruticosa in Open Pit Coal Mine Areas

[Objective] To explore the water use characteristics of typical plants under different ecological measures at the waste dump, improve plant water use efficiency, and accelerate the ecological restoration process in mining areas. [Methods] Six ecological measures (control, inoculation, green fertilizer, inoculation+green fertilizer, inoculation+weathered coal, inoculation+green fertilizer+weathered coal) were implemented at the waste dump of the Heidaigou Coal Mine to treat Amorpha fruticosa. Stable isotopes of hydrogen and oxygen in water were combined with other techniques. [Results] (1) The soil moisture content of the waste dump was 3% to 9%, which was lower in the 0-30 cm and 70-100 cm soil layers, and higher in 30-70 cm soil layer. (2) Amorpha fruticosa obtained water from precipitation and soil. The soil water undergoes significant fractionation processed in the 0-30 cm soil layer, and exhibited significant differences among different ecological measures, with the green fertilizer treatment showing the