Evaluation and analysis of cascading spread caused by multisource dust migration in a pollution-related ecosystem.

The migration and settlement of dust from different mining areas forms pollution-related network. In order to describe the problem of cascading spread in pollution-related network, a new object function colored GeoPetri net model was proposed that uses colored PNs to distinguish different pollution sources. Based on the HYSPLIT model, the long-distance migration path and settlement of dust are simulated by clustering trajectory and spatial distribution of deposition. Three relationships and dynamic indicators are designed in the model. Taking four coal fields in China as case studies, the process of cascading spread, the impact of correlation on vulnerability, and the impact of ecological thresholds on scale are analyzed. The results show that the subsystems of mining areas are generally more vulnerable than other subsystems. Composite subsystems as a whole are less vulnerable than others. The results also show that the vulnerability of subsystems is more affected by the external association of subnets than by intranet element association. The results demonstrate that, based on the relationship between pollution load and ecological threshold, it is worthwhile to make reasonable investments in production costs. It is of great significance for the joint prevention and emission reduction to study the problem of simultaneous emission from multiple sources in pollution-related network.