A reliable ecological vulnerability approach based on the construction of optimal evaluation systems and evolutionary tracking models

Ecological vulnerability assessment is an effective means to monitor ecosystem stability, and its application has been an emerging hotspot. Although some progress has been made in the study of ecological vulnerability, there are few studies on the accuracy of the evaluation index and the tracking of the evolution process. Therefore, this study discussed the impact of the improved ecological vulnerability assessment index system and spatial scale on the ecological vulnerability of the target area, and conducted a confirmatory analysis of it. Taking Weinan City, a typical city in the Yellow River Basin as the research object, the evolution tracking model of ecological vulnerability was established, and the internal relationship between the dimensions of impact factors and ecological vulnerability index (EVI) was analyzed. The results showed that (1) the correlation between EVI and NDVI of the optimized index system (e) (ISe) was −0.793, and the R-value of linear fitting was 0.63, which indicated that the optimized evaluation results were closer to the actual situation. (2) From 1999 to 2019, the overall ecological condition of Weinan was positive, with the distribution characteristics of low EVI in northern and southern mountain cities and high EVI in central plain cities. (3) Hierarchical transformation of EVI in the combination area where ecological vulnerability remained stable and degraded accounted for 75.24%, indicating that the overall evolution direction of ecological vulnerability changed to a good direction. The results can provide an effective way to optimize and validate the ecological vulnerability assessment system and track the evolution of ecological vulnerability effectively.