## 3 Results
### Decoupling Analysis  
Based on the five-year plan, Henan's SIUS were decoupled in five phases. Table 1 shows the decoupling index between Henan's SIUS and the economy. From 2000 to 2023, both GDP and SIUS maintained a growth trend (i.e., \(\Delta\)GDP/GDP > 0; \(\Delta\)MS/MS > 0). The decoupling index continued to increase to 0.65, but it showed a downward trend after the 11 th Five-Year Plan. This result indicates that SIUS and economic growth are in a state of weak decoupling, with the correlation between economic growth and SIUS gradually weakening. This means that during this phase, while economic growth continued, the growth rate of SIUS slowed in comparison to GDP growth. Since the 21 st century, China's rapid industrialization and urbanization have stimulated both economic and SIUS  
Figure 7: Local spatial autocorrelation of per capita SIUS. growth. However, with technological advancements, progress in the circular economy, and adjustments in industrial structure, the close relationship between economic growth and SIUS has weakened, thereby mitigating environmental pressures. In order to further clarify the internal factor of the change in the decoupling index, the Tapia-LMDI model was used to decompose the decoupling index. And the decoupling index can be divided into three factors (See Figure 8):  
1. The affluence factor is the most significant disincentive to decoupling. Its contribution to the decoupling index reached 0.51 during the 10 th Five-Year Plan period but sharply dropped to just 0.008 in the early 14 th Five-Year Plan period. According to _the Outline of China's 14 th Five-Year Plan_, China's economy should maintain an average annual growth rate of above 5% in the second half, while Henan's 14 th Five-Year Plan has set a target of 6%. This suggests that the driving role of affluence will be weakened. Although the affluence factor is declining, it remains an important factor influencing decoupling. 2. The population scale factor exerts a noticeable inhibitory effect on the decoupling state, although its influence on the decoupling elasticity index is relatively weak. Overall, this effect has demonstrated a downward trend over time. The effect of the population scale factor is predominantly demonstrated through rural-urban migration. With the aim of accommodating more people, the government needs to build large quantities of buildings and infrastructure, thereby increasing resource consumption. Henan's population has been on an upward trend, growing from 94.66 million in 2000 to 99.41 million in 2020, and then declining to 98.15 million in 2023. Notably, during the transition from the 13 th to the early 14 th Five-Year Plan periods, a population decrease of 1.66 million occurred. This decline in population scale alleviated the pressure on resource consumption, effectively promoting the decoupling process. Consequently, the population scale factor might contribute to achieving decoupling in the future. 3. The technological factor positively drives the decoupling process, despite its contribution rate being \(-\)5%. As [PERSON] et al. (2023) noted, the decrease in the utilization intensity of SIUS is quantified as a negative value in the model [43]. This seemingly contradictory negative value actually reflects improved efficiency in steel resource utilization. As illustrated in Figure S2, the utilization intensity of SIUS has been on a downward trend, decreasing by 24% annually. This decline evidently shows that technological advancements have facilitated more efficient utilization of SIUS, thereby reducing the steel requirement per unit of economic output. The negative contribution rate, rather than indicating ineffectiveness, precisely underscores the pivotal role of technological progress in offsetting the growth in steel consumption induced by other factors, thereby accelerating the decoupling process.