金属是支持社会经济发展的重要材料，对我国的基础设施建设、制造业等行业至关重要。与此同时，金属的大量的生产和消费不仅引发了大量的碳排放，也引发了一系列的环境问题，对人体健康造成威胁。从消费侧角度出发，探究我国金属足迹的演变规律及其与碳排放之间的影响关系，并对金属足迹的达峰值和达峰时间做出预测，有助于更好地理解我国的金属消费需求、提高金属消费效率。本研究基于多区域投入产出模型，对我国1995至2022年的金属足迹进行了核算，进一步分析了其与各社会经济变量之间的关系，并对金属足迹的达峰时间做出了预测。

1995至2022年，我国金属足迹总体呈现出上升的趋势，但是在2014至2018年有所波动。在金属足迹的构成上，铁矿石和铜矿石是最主要的贡献因素；在金属足迹的最终需求结构上，投资是拉动金属足迹主导因素。在敏感性方面，总体上我国金属足迹对人均GDP、资本形成总额和固定资本形成总额的弹性是显著的；单个金属对于研究中涉及到的5个社会经济变量的均是敏感的。

在金属足迹与碳排放的关系上，金属足迹引发的碳排放和总碳排放都呈现出逐年上升的趋势，但前者增长较慢。因此，金属足迹引发的碳排放占总碳排放的比例在逐渐下降。1995至2018年，我国金属足迹与总碳排放呈现出了弱脱钩的关系。在本研究涉及的43个国家和地区中，有30个国家的金属足迹与碳排放显著相关（包括中国），在部分国家，金属足迹、碳足迹和碳排放三者都是具有较强相关关系的。

在本研究涉及的43个国家和地区中，有13个国家已经实现了金属足迹的达峰，而我国金属足迹仍然处于上升期，短期内没有达峰的迹象。与全球其他国家和地区，尤其是发达国家相比，我国处于一种“较高人均金属足迹，较低社会经济发展水平”的状态，且这一状态短期内不会有太大改变。此外，本研究借助STIRPAT模型，设置了三种情景，对我国金属足迹进行了达峰预测。结果显示，在这三种情景下，我国金属足迹将分别于2047年、2046年和2046年达峰。

Metals are important materials that support socio-economic development and are vital to our infrastructure construction, manufacturing and other industries.At the same time, the massive production and consumption of metals has not only caused a large amount of carbon emissions, but also a series of environmental problems that pose a threat to human health.From the perspective of the consumption side, we explore the evolution pattern of China's metal footprint and the relationship between it and carbon emissions, and make predictions on the peak and peak time of the metal footprint, which will help to better understand China's metal consumption demand and improve the efficiency of metal consumption.Based on a multi-regional input-output model, this study accounts for the metal footprint of China from 1995 to 2022, further analyzes its relationship with various socio-economic variables, and makes predictions on the time to peak of the metal footprint.

From 1995 to 2022, China's metal footprint shows an overall upward trend, but fluctuates from 2014 to 2018. In the composition of the metal footprint, iron ore and copper ore are the most important contributors; in the final demand structure of the metal footprint, investment is the dominant factor pulling the metal footprint.In terms of sensitivity, overall the elasticity of our metal footprint to GDP per capita, gross capital formation and gross fixed capital formation is significant; individual metals are sensitive to all five socioeconomic variables involved in the study.

In the relationship between metal footprint and carbon emissions, both carbon emissions induced by metal footprint and total carbon emissions show a rising trend year by year, but the former grows more slowly. Therefore, the proportion of carbon emissions induced by metal footprint to total carbon emissions is gradually decreasing. From 1995 to 2018, China's metal footprint showed a weak decoupling relationship with total carbon emissions. Among the 43 countries and regions covered in this study, 30 countries have a significant correlation between metal footprint and carbon emissions (including China), and in some countries, all three of metal footprint, carbon footprint and carbon emissions are strongly correlated.

Among the 43 countries and regions covered in this study, 13 countries have already reached the peak of their metal footprint, while China's metal footprint is still on the rise, and there is no sign of reaching the peak in the short term. Compared with other countries and regions around the world, especially developed countries, China is in a state of "higher metal footprint per capita and lower socio-economic development", and this state will not change much in the near future. In addition, this study set up three scenarios with the help of STIRPAT model to predict the metal footprint of China to reach the peak. The results show that under these three scenarios, China's metal footprint will peak in 2047, 2046 and 2046, respectively.