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Nowadays, the challenges of energy depletion, environmental pollution and food security caused by extensive agriculture development are attracting global attention. In China, the construction of ecological farms is a key initiative to effectuate the goal of peaking carbon dioxide emissions and achieving carbon neutrality, contributing to high-quality agricultural development. Based on this, this study selects the national-level ecological farms directories issued by the Ministry of Agriculture and Rural Affairs (MARA) of China in 2021 and 2022, and collects the corresponding economic, social and physical geographic data for GIS spatial analysis and Geodetector. The results are as follows: (1) The distribution of ecological farms in various provinces of China is uneven and spatially clustered. It generally presents a 'high in the east and low in the west with concentrated cores' pattern. The construction scope significantly expanded over time, and the high-value areas of nuclear density are concentrated in East China, with the development core transitioned from East China to Central China. (2) Environmental conditions, industrial foundation, economic and social development level, science and technology level and financial support all significantly affect the spatial distribution of ecological farms in China, among which the science and technology level has the most significant enhancement effect on other factors. (3) Environmental conditions provide the construction basis for ecological farms, while economic and social development level and financial support determine the number of ecological farms. The industrial foundation affects the scale of ecological farms in China, while the level of science and technology eliminates the restrictions of other factors to a certain extent. This study provides a reference for optimizing the spatial distribution pattern of ecological farms in China and promoting ecological agriculture. In addition, it presents a viable approach to safeguarding food security. [ABSTRACT FROM AUTHOR]

Achieving carbon neutrality in China critically depends on the successful decarbonization of its iron and steel sector. While previous studies have primarily focused on improving technology performance in steel production processes, the potential CO 2 reduction through material efficiency strategies for steel demand management remains largely unexplored. To bridge this research gap, this study aims to quantitively assess the co-benefits of CO 2 reduction from implementing energy and material efficiency strategies along China's steel flow chain. By integrating dynamic steel flow analysis with a CO 2 accounting model, this model traces energy use, material flows, and CO 2 emissions along the steel flow chain, then evaluates the CO 2 reduction potential of implementing various mitigation strategies by 2060, and finally quantifies the relative contribution of each strategy. The findings indicate that the coordination of energy and material efficiency strategies can reduce CO 2 by more than 80% from the business-as-usual level by 2060. In particularly, the strategies of more recycling, longer lifetimes, and energy efficiency improvements are projected to contribute −68%, −43%, and −11% of CO 2 reduction, respectively, even amidst an expected +29% rise of CO 2 emissions driven by economic growth. The study can provide more promising options for decarbonizing China's iron and steel sector and lays the foundation for future analyses that seek to integrate demand-side material efficiency strategies in China's steel decarbonization modeling. [Display omitted] • Incorporating material efficiency strategies in China's steel decarbonization modeling • Proposing a model that integrates dynamic steel flow and CO2 accounting model • Coordinated energy and material efficiency strategies is key to decarbonizing CISS • Material efficiency strategies are expected to play key roles in decarbonization • Longer lifetimes, recycling, and energy efficiency contribute significantly [ABSTRACT FROM AUTHOR]

China's iron and steel sector has experienced a significant rise in CO 2 emissions over recent decades, largely due to complex interplays among energy use, material demand, and economy growth along the steel flow chain. Understanding these interconnected drivers is crucial for effective decarbonization policies. To address this issue, this study integrates extended input-output analysis, material flow analysis, and CO 2 accounting to quantitatively assess the relative impacts of these drivers within the energy–material–economy nexus. The concept of exergy is introduced to account for heterogeneous energy and material flows within the nexus. The findings highlight the primary narrative behind CO 2 growth in China's iron and steel sector: substantial investments facilitated construction sector expansion, subsequently driving up crude steel production via blast furnace routes and escalating CO 2 emissions due to extensive coke use. Historical decomposition analysis from 2002 to 2017 underscores construction sector investments as the primary driver of CO 2 growth, while energy efficiency improvements in steel production processes progressively contribute to CO 2 reduction. Nevertheless, efforts to shift steel production routes for CO 2 reduction are challenged by limited scrap supply. Furthermore, the analytical approach holds potential for investigating the underlying narrative and drivers of CO 2 growth in other metal sectors across China. [Display omitted] • An integrated analysis of energy–material–economy nexus for CO 2 growth in CISS. • Exergy was introduced to integrate heterogeneous energy and material flows. • Main narrative includes investment, construction sector, crude steel, BF, coke, and CO 2. • Substantial investment in the construction sector is the major driver for CO 2 growth. • Steel production route adjustment didn't work due to limited scrap supply. [ABSTRACT FROM AUTHOR]

Improving energy efficiency is one of the most reliable ways toward carbon neutrality. Most previous studies have focused on how to reduce energy intensity; however, it is not enough to provide an overview of how many carbon emissions can be reduced by technical efficiency improvements underlying energy systems. To fill this gap, this study extended the common Kaya identity to systematically evaluate the carbon reduction potential from technical efficiency improvements of various technical conversion components within the energy system at a granular level. The extended Kaya identity includes technical efficiency factors of electricity efficiency, conversion efficiency, and passive efficiency. It provides a comprehensive framework to evaluate current performance, historical contributions, and future potential of technical efficiency improvements. The case of China reveals that: Currently, only around 5% of energy sources were delivered to final services. By improving technical efficiency to high levels, 59% carbon reduction can be achieved during the future energy transition, even when the economy is still growing. In the past, electricity efficiency and conversion efficiency have significantly reduced carbon emissions. Future policymakers should pay more attention to passive systems to provide more final services, such as improved room insulation, streamlined vehicle designs, and smart energy management. • Proposed an extended Kaya identity framework for the systematic evaluation. • Evaluated the role of technical efficiency improvements at the most granular level. • 59% carbon reduction by improving technical efficiency during energy transition. • Passive systems highlighted for more carbon reduction potential. • Strongly promoting technical efficiency improvements in China's carbon neutrality. [ABSTRACT FROM AUTHOR]