Marine ecological protection is an important development basis for China's ocean green development. On the one hand, it can provide sustainable resources and environment for green development. On the other hand, it can enhance the carbon sink capacity of the ocean and strengthen green development in achieving China's "double carbon" goals. This paper systematically reviews the current situation and challenges of China's marine ecological protection, including sub-health status of most marine ecosystem, threat of marine environmental hazard, depletion of fishery resources, high risk of coastal development and lack of marine ecological restoration funding. Based on these situations, this paper proposes the strategic goals for China's marine ecological protection. Finally, from the perspectives of space management, financial guarantee, system improvement and marketization of carbon sink, this paper puts forward the development path of China's marine ecological protection to fulfill green development.

In this article, the role of CO₂ geological sub-seabed storage in the field of climate change is discussed, as well as the development trends of CO₂ geological sub-seabed storage in China and abroad. Furthermore, countermeasures for the development of this technology are proposed. From the aspects of geological structure characteristics and coastal industrial layout, China has the advantages of developing CO₂ geological sub-seabed storage. A large number of foreign engineering applications have proved the feasibility and effectiveness of the technology. In recent years, engineering practices have also been launched in China. CO₂ geological sub-seabed storage has been subject to the jurisdiction of international conventions, and some developed countries have established special management systems. Combined with China's overall positioning for the development of CO₂ geological sub-seabed storage based on carbon peak and carbon neutrality goals, the possible challenges in the future are elaborated and corresponding countermeasures are proposed.

Study on the decoupling relationship between transport carbon emission and economic growth is of great practical significance for achieving the goals of carbon peaking and carbon neutrality. This paper mainly uses a "bottom-up" transportation carbon emission calculation method to calculate the annual transportation carbon emission of railways, aviation, water, and roads in China and various provinces. It analyzes the spatiotemporal changes of China's transportation carbon emission from 2000 to 2020, and uses the Tapio decoupling models to explore the decoupling status of China's transportation carbon emission. It is found that (1) From 2000 to 2020, the total carbon emission from China's transportation increased from 237.7441 million tons to 1390.5147 million tons. The period from 2004 to 2011 was a period of rapid growth, and the growth rate began to slow down after 2012; (2) From 2000 to 2020, road carbon emission was the main source of carbon emissions in China's transportation, with a slight increase in the proportion of carbon emission from air transportation and a significant decrease in the proportion of carbon emission from railways and waterways; (3) From 2000 to 2020, there were significant regional differences in transportation carbon emission in the four major regions of eastern, central, western, and northeastern China; (4) From 2000 to 2020, the carbon emissions and economic development of China's transportation industry showed an overall trend of "relative decoupling", with most provinces including Beijing and Shanghai achieving "decoupling".

The green development of China's logistics industry is a key area for the carbon peaking and carbon neutrality goals. This article combines the connotation of green development in the logistics industry to study and construct a green logistics development level indicator system. Based on the carbon emissions inventory and statistical yearbook data of China's provincial-level transportation, logistics, and warehousing industry from 2014 to 2019, factor analysis was used to reduce the dimensionality of green logistics development indicators to form 8 influencing factors. A geographic weighted regression model was applied to explain the provincial differences and spatiotemporal evolution patterns of the driving factors of carbon emissions intensity in China's logistics industry. The study found that during the sample investigation period, the carbon emission intensity of China's logistics industry at the provincial level showed an aggregation phenomenon of weakening year by year, and showed a basic spatial differentiation pattern of "strong in the west and weak in the east". The factor center of gravity showed a trend of shifting from the east to the central region. The factors of extensive logistics development and logistics equipment have the strongest positive effects on carbon emission intensity, while the factors of energy cleanliness, freight structure adjustment, and innovation have inhibitory effects. Based on the analysis results and the resource endowments and development strategies of each province, policy implications for the development of green logistics in China were proposed.

As the main field for carbon emission reduction, megacities play a key role in the green transformation process. Based on the dual challenges of high-quality development and "Dual-Carbon" goals of megacities, this paper focuses on the two levels of carbon reduction and carbon fixation, systematically builds the method for the target of "Carbon Peak and Neutrality" with the joint promotion of energy transformation and resources efficiency as well as the mutual support of carbon sequestration technology innovation and ecological carbon sink, carries out the strategy research based on the low-carbon transformation of energy structure, resilient development of urban upgrade, quality improvement of ecological system and green reconstruction of transportation system, and aims to provide valuable reference in regard of the promoting low-carbon development of megacities and realizing the national strategic goal of "Dual-Carbon".

Transition to "cleaner" electricity is crucial to achieving the target of carbon peak and carbon neutrality in China and it depends on structure optimization. In this study, a multi-objective model is established to optimize electricity structure in Fujian province under three carbon sink scenarios in 2060. The results show that: (1) Currently, the thermal power still dominates the electricity generation, the hydropower has peaked, the nuclear power is increasing, and the other sources (e. g., wind, solar, biomass) begin to grow. (2) Under the optimal carbon emission scenario, Fujian province has to increase its installed capacity of electric power to 255 million kilowatts, rapidly develop renewable energy, and widely apply energy storage batteries in 2060. (3) Under the optimal power structure scenario, Fujian province would need to increase its installed capacity of electric power to 180 million kilowatts and form a balanced source of electricity. (4) Under the optimal power structure stability scenario, the installed capacity of electric power merely has to reach 205.5 million kilowatts, but the costs on construction and upgrading of the Carbon Capture Utilization and Storage (CCUS) technology would be very high. In summary, the coverage of CCUS higher than 82% and the annual natural carbon sink "quota" of electricity sector exceeding 26.2 million tons are two thresholds for Fujian province to form a renewable and "clean" electricity and achieve carbon neutrality in 2060.

The digital economy has become a leading force in building national competitiveness and promoting green economic development. As the leading industry of the national economy, the manufacturing industry undergoes green transformation, which is an important way for high-quality economic development. This paper systematically discusses the important role of digital economy as a new economic form in empowering traditional industries and promoting deep integration among various industries, and it summarizes the development trend and strategic layout of digital economy in countries such as the United States, the United Kingdom, and Japan. Finally, it proposes thoughts and suggestions based on the practice of digital transformation and green development in China's manufacturing industry.