Quantitative correlations between soil and plants in reclaimed mining dumps using a coupling coordination degree model

It is generally accepted that coevolution between soil and plant has great significance for the sustainable development of mining dumps in fragile eco-environment. However, this was not very clear in opencast mine area located in Western China. Based on comprehensive index systems and a combination of subjective and objective weighting method, a coupling coordination degree model, including comprehensive evaluation function, coupling degree and coupling coordination degree, was established to find the 'short plank' of different reclamation patterns and to quantify the status quo of coevolution between soil and plant systems in mined plots. The results indicated that only the plot with Pinus tabuliformis was under synchronous development, a mixed model of Robinia pseudoacacia-Pi. tabuliformis and R. pseudoacacia monoculture were developed with vegetation lagging, while plots R. pseudoacacia-Ulmus pumila-Ailanthus altissima and original landform were soil lagged. All plots were in the state of primary and intermediate coordination. Thus, some effective measures should be taken for the further development in different patterns.