Physical-chemical Characteristics and Moisture Characteristics of Substrates in Different Eroded Microhabitats of Weathered Gangue Dumps

Abstract

[Objective] The physical and chemical properties and water characteristics of substrates under different eroded microhabitats were studied to provide a theoretical basis for understanding the driving and limiting mechanisms of vegetation settlement and restoration, and to provide scientific references for the practice of vegetation reconstruction in early abandoned mining areas in the North China. [Methods] The mechanical composition, bulk density, capillary porosity, pH value, electrical conductivity, and moisture characteristics of bare slopes, rills, shallow gullies, and deposit bodies were studied, and the relationships between them were analyzed. [Results] Particle size matrices varied among different eroded microhabitats, and there were differences among different soil layers. The bulk density of the substrates in different eroded microhabitats followed the order of shallow gully>rill>bare slope>deposit body, while capillary pore size followed the order of deposit body>bare slope>shallow gully>rill. There were no significant differences in the pH value of different eroded microhabitats, but there were differences in the changes in different soil layers. Electrical conductivity followed the order of deposit body>bare slope>shallow gully>rill, and was higher in the 10—20 cm soil layer than in the 0—10 cm soil layer. The matrix moisture content and capillary water capacity of different eroded microhabitats followed the order of deposit body>bare slope>shallow gully>rill. The matrix moisture content and capillary water capacity of the bare slope and the shallow gully were the lowest on the upper slope, while they were lowest for the rill on the middle slope. [Conclusion] The substrate moisture characteristics of weathered gangue dumps were significantly affected by bulk density and capillary porosity. There were relatively more sand and medium-coarse grain particles in bare slopes and deposit bodies of weathered gangue dumps, and the moisture characteristics were superior. Bare slopes and deposit bodies can provide a safe habitat for vegetation settlement and restoration.

Keywords

• weathered gangue dumps
• eroded microhabitats
• mechanical composition
• physical-chemical properties
• moisture characteristics