Identifying ecological priority protection and restoration areas based on the changing characteristics of ‘past-future’ Ecological Security Patterns: a case study of Nanning

Accurately identifying potential ecological degradation areas and key ecological function areas based on the Ecological Security Pattern (ESP), incorporating them into the core scope of ecological restoration and optimization strategies, is crucial for enhancing the efficiency and targeting of ecological restoration efforts. However, previous studies adopted a single, relatively static perspective to study ESP, which limits the effectiveness of ecological restoration efforts. Taking Nanning as a case study, we constructed its ESP for 2000, 2010, and 2020 using the Patch-based Land Use Simulation (PLUS) model and circuit theory. We also simulated ESP under four 2030 future scenarios: the natural development scenario (NDS), ecological protection scenario (EPS), urban development scenario (UDS), and cropland protection scenario (CPS), By comparing temporal and scenario-based ESP changes, we identified Nanning's ecological priority protection areas (EPPAs) and ecological priority restoration areas(EPRAs). The primary results are as follows: (1) From 2000 to 2020, Nanning's construction land area exhibited a growth rate of 47.06%, while the ecological land area continued to decrease. This trend is projected to persist under the four scenarios in 2030, particularly under the UDS, which shows a growth rate of 27.27% in construction land compared to the level in 2020. (2) Nanning's ESP was continuously degraded from 2000 to 2020, leading to a 185.40 km 2 reduction in ecological source areas, a 70.73 km increase in ecological corridor length, a 167.56 km 2 expansion of ecological pinch points, and a 117.40 km 2 growth in ecological barrier points. These changes led to the contraction of species habitats, increased migration costs, and disruption of the ESP. (3) In 2030, ESP conditions improve under NDS and EPS, with the improvement being more pronounced under EPS, where ecological source areas increase by 22.91 km 2 compared to 2020. In contrast, UDS and CPS cause further damage to the ESP, with the most severe impact under UDS, where ecological source areas decrease to a historical low of 11,321.7 km 2 . (4) Leveraging the spatial and quantitative changes in the “past-future” constructed ESP, we precisely identified EPPAs and EPRAs, and proposed corresponding strategies: land-use planning, policy interventions, and ecological engineering measures. In addition, this study found that the Nanning's topography shapes unique short and long ecological corridors. This study offers new insights for ecological rehabilitation in Nanning, it also provides new perspectives for other studies. • We constructed a study framework for analyzing Ecological Security Patterns covering the past and future. • We Optimized a methodology for identifying ecological priority areas for protection and restoration based on Ecological Security Patterns. • We constructed the Ecological Security Patterns of Nanning for the years 2000, 2010, and 2020, as well as for four future development scenarios in 2030. • We discussed the formation factors of short and long ecological corridors.