Research and Application of Water Security Evaluation Model Based on Improved Petri Net

This study addresses the inadequacy of traditional water quality safety warning models in responding to sudden water pollution incidents by proposing an improved model based on the Petri net transition ladder theory. By integrating the leap-step factors of Petri nets into the Analytic Hierarchy Process (AHP) and fuzzy comprehensive evaluation method, a dynamic water quality safety evaluation system was constructed, overcoming the limitations of traditional methods in promptly reflecting abrupt changes in indicators due to inherent weighting mechanism flaws. Using City A’s No. 1 River as a case study and incorporating water quality monitoring data from 2021 to 2023, the effectiveness of the Petri net model was validated. The results demonstrate that the improved model significantly enhances sensitivity and accuracy in detecting sudden pollution events. Notably, it can rapidly trigger early warnings when indicators such as total phosphorus deteriorate, hereas traditional methods fail to capture such changes. This research provides new theoretical support for water quality safety warnings and offers a scientific basis for practical water pollution prevention and control in City A’s No. 1 River.