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[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 highest and inoculation+green fertilizer treatment being the lowest. (3) Significant differences existed in the water use characteristics of Amorpha fruticosa under various ecological measures. The inoculation treatment exhibited a higher water use ratio of 53.4% in the 50-100 cm soil layer; The green fertilizer treatment mainly utilized the soil water in the surface layer (0-20 cm), which was 42.6%; The treatment of inoculation and green fertilizer had a relatively uniform proportion of soil water use in each layer. [Conclusion] The inoculation + green fertilizer treatment optimized the water use characteristics of Amorpha fruticose plants, increased the utilization ratio of surface and deep soil water, and can be used as an ecological reclamation measure for waste disposal sites, which promoted the ecological recovery rate and effect of arid mining areas in the western region.

Coal mining has formed open-pit dumps and underground subsidence areas, changing the original landform and ecology. The instability of the open-pit dump slope is easy to cause soil erosion, which causes the landslide to shear the vegetation root system. The underground subsidence causes the ground fissure to develop and damage the plant root system. Therefore, one of the keys to mine ecological restoration is to enhance the shear resistance and strain resistance of plant roots. Microbial reclamation has the functions of improving soil physical and chemical properties, promoting plant root development and stress resistance. The effect of inoculation on the shear and tensile resistance of root-soil complex is have laid a good foundation for revealing the mechanism of mine ecological restoration. After artificial restoration, plant roots and soil to form a root-soil complex, which can greatly increase the shear strength of the soil, enhance the stability of the shallow soil, effectively reduce the soil and water loss of the slope of the open-pit dump and relieve the root starin. Arbuscular mycorrhizal fungi (AMF) or dark septate endophytic fungi (DSE) are ubiquitous in the rhizosphere, and their mycorrhizal symbionts formed with roots are bonded to the rhizosphere soil to form a root-soil complex. There are few studies on the mechanism and influencing factors of shear resistance. Therefore, the influencing factors, mechanism of action and ecological restoration potential of root-soil complex inoculated with microorganisms in mining areas are reviewed in this artical. At the same time, combined with the analysis of experimental data, it is concluded that the underground biomass, soil cohesion and shear strength of root-soil composite soil inoculated with AMF and DSE are significantly improved. Microbial reclamation technology not only improves the survival rate and stress resistance of artificial restoration vegetation.

Community density of grassland has obvious impacts on the absorption, sequestration, and accumulation of soil carbon (C). However, few studies have examined the effect of community density on soil C dynamics and their internal driving forces after cropland abandonment. Here, we synthesized the responses of soil C to community density of grassland over a 45‐year time‐sequence along a natural restoration time sequence. The results showed that the soil C content during the late‐successional period was greater than that during the early‐successional period, that is, annual C storage rates for the first sequence (1–15 years) for the 0–60 cm depth profiles were −0.34, −0.27, −0.15 to 0.02 Mg‐C ha−1 yr−1, in the ≤10, 11–20, 21–30, and >30 community densities. And the third sequence (31–45 years) presented values that were 79.28% and 44.60% greater than those of the initial stage of vegetation restoration (CK) for the 0–20 and 0–60 cm profiles, respectively. The increased soil C storage rates of the late‐successional sequence were associated with both increased aboveground production and root biomass for this sequence and the presence of multiple species, especially Leguminosae and Gramineae species, with developed roots. Overall, the effects of community density on soil C were regulated by the recovery time, root mass, and species genera. Furthermore, our results suggest that soil may still be a carbon source even after 15 years of the abandonment restoring, and high community density may greatly increase C capture and storage rates in abandoned lands. The findings enhance the understanding of soil C sequestration and accumulation responses to community density following long‐term natural vegetation succession, providing support for estimating and predicting the regional C budget and global C cycle. [ABSTRACT FROM AUTHOR]