Ecological carrying capacity assessment of large-scale open coal mines in loess zones- A case study of Antaibao Opencast Mine in Pingshuo

Change in Ecological Carrying Capacity (ECC) in open coal mines is closely related with pollution control, land reclamation and ecology rehabilitation measures. Based on connotation and hierarchical characteristics of ecological carrying capabilities of mines (MAECC), a quantified assessment method of MAECC involving ecosystem resilience, resource and environment carrying capacity, and ecosystem stress is put forward. The unified ecological carrying capacity appraisal method proposed by Gao Jixi, combined with an established index assessment system with the index weight decided by AHP, was used for static and dynamic appraisal of the MAECC. The ecosystem resilience of Antaibao Opencast Mine ecosystem in Pingshuo is 46.836 for 2007 - which is described as moderately stable. Environment carrying capability is 47.127 - which is medium load bearing. The ecosystem stress is 1.396 - which is excess load bearing. Based on the change dynamics, there is a drastic change in ecosystem resilience. This shows that the stability of the ecosystem in mining areas is weak with obvious frail characteristics. The change in ecosystem stress index implies a greater impact of ecosystem stress on the resilience of the ecosystem and the carrying capacity of mine area resource and environ-ment before 1999. This impact has gradually weakened since 1999. This conclusion is also true for the trend of ecosystem resilience, resource and environment carrying capacity of mining area for 1987～2007. The resilience of the ecosystem began rising after 1997 along with a significant increase in the carrying capacity of the resources and the environment after 1999.