The study of the input–output efficiency and influencing factors of forest carbon sinks is beneficial for the realization of the rational allocation of forest carbon sink resources. Based on the DEA-SBM model, the efficiency of forest carbon sinks is measured and analyzed in 30 provinces (cities) of China from 2005 to 2018; the influencing factors of forest carbon sink efficiency are constructed from the three perspectives of pressure subsystem, state subsystem, and response subsystem with the help of the PSR model and regression analysis is conducted using the FGLS model so that the results of the study can provide a basis for formulating a regionally differentiated forest carbon sink system. The empirical results show that the average annual forest carbon sink efficiency in China is only 0.29, and there is much room for improvement. The level of urbanization, the degree of natural damage to forests, precipitation, and the proportion of financial support for forestry are positively correlated with forest carbon sink efficiency, while temperature is negatively correlated with forest sink efficiency. Additionally, different influencing factors have regional heterogeneity on forest carbon sink efficiency. Based on the above findings, we propose the following policy recommendations: formulate forest carbon sink strategies according to local conditions, adjust and optimize the forestry industry structure at the right time, minimize the intervention in forest ecosystems, improve the supervision mechanism of special forestry funds, improve the level of forestry human capital, and accelerate the transformation of scientific and technological achievements.

As regional interaction increases in an open economy, a region’s green total factor productivity in agriculture must be considered alongside relationships with other regions. In this study, the slack-based model (SBM) global Malmquist–Luenberger (GML) index is used to measure the green total factor productivity of agriculture in each province of China, and the social network analysis (SNA) and vector autoregressive model (VAR) impulse response function (IRF) are used to examine the spatial network structure and regional interactivity. The research confirms that the absolute value and concentration of agricultural green total factor productivity are generally higher in the south than in the north of China, but the peak is lower in the south than in the north. The network density of agricultural green total factor productivity in China from 2008 to 2019 shows an increase, with the cut-off values of mean, 10, 50, and 100 treated as 4.97%, 2.57%, 3.30%, and 2.43%, respectively. From 2008 to 2019, the central potentials of network entry and network exit of green total factor productivity in China’s agriculture show a “V”-shaped and inverted “V”-shaped evolution path, respectively, with the density of cohesive subgroups growing, which demonstrates that the spatial structure of green total factor productivity in Chinese agriculture has experienced an evolutionary path from polycentric to monocentric to polycentric conditions. The spatial interaction of different cohesive subgroups is intensifying and has a certain degree of self-stability. In terms of regional interaction, the siphon effect of the east on the green development of agriculture in the central and western regions is significant, but the trickle-down effect is not obvious, and the interaction between the central and western regions has a catalytic effect on the efficiency of the green economy of agriculture in both regions. It is recommended that targeted policies be introduced to support the flow of agricultural factors and industrial division of labour between the central and western regions and the south and north, taking into account the actual situation. The novelty of this paper is that it focuses on the green total factor productivity of Chinese agriculture and combines the innovative use of the social network analysis paradigm to analyse the green development of agriculture in a country from a spatial dynamic evolutionary perspective. A limitation of the research methodology in this paper is its poor applicability to closed economy analysis.

The CO₂ emissions from marine fisheries have a significant impact on marine ecology, despite generally being overlooked in studies on global climate change. Few studies have estimated the carbon emissions from marine fisheries while taking into account all pertinent sectors. This study evaluated marine fisheries’ CO₂ emissions based on three sectors: marine fishing, mariculture, and the marine aquatic product processing industry. Kernel density estimation and the spatial Durbin model were used to investigate the spatial and temporal characteristics and the key socioeconomic drivers of the CO₂ emissions from marine fisheries in 11 coastal provinces of China from 2005 to 2020. The results are as follows: (1) marine fishing is the sector that produces the most CO₂ emissions; trawling operations generate more CO₂ than all other modes of operation combined; (2) China’s marine fisheries’ CO₂ emissions show a rising, then declining, trend, with significant differences in coastal provinces; (3) the development of the marine fishery economy and trade have a positive driving effect on CO₂ emissions, the expansion of the tertiary industry does not decrease CO₂, the technical advancement and income growth of fishermen are negatively related to carbon emissions, and the effect of environmental regulation has failed to pass the significance test; (4) the carbon emissions of marine fisheries have significant spatial spillover effects.

A more scientific green economy efficiency indicator is constructed based on OH (2010), and a multiperiod spatial DID model is used to examine the impact of national credit demonstration policies on urban green economy efficiency in a sample of cities above the prefecture level in the Yangtze River Delta. The study confirms the following: (1) The national credit demonstration policy makes a significant contribution to the green economic efficiency of cities, and it is conducive to strengthening awareness of the rule of law in the market to regulate market order. (2) The demand for credit regulation in coastal areas has increased under the new development pattern, and the national credit demonstration policy has effectively enhanced green economy efficiency through institutional supply. (3) Under the national credit demonstration policy, the subprovincial level and above can mobilise more resources for policy refinement and support, reducing transaction costs and improving the efficiency of the green economy. (4) The impact of the national credit demonstration policy on the efficiency of Zhejiang’s green economy is more obvious; but, under the overall framework of the Yangtze River Delta, the policy has a more prominent role in promoting green economy efficiency in other provinces. Policy insights are as follows: (1) Different cities have different degrees of impact on the efficiency of the green economy from the national credit demonstration policy, and they should implement differentiated measures based on regional heterogeneity; (2) regulating the use of administrative resources and avoiding undue administrative intervention are important prerequisites for promoting regional integration to enhance the efficiency of the green economy; and (3) strengthening interprovincial credit policy synergies can help to alleviate administrative distortions of policy implementation and enhance the efficiency of the regional green economy.

Based on the China City Commercial Credit Environment Index (CEI), a more scientific spatial DID model was used to examine the long-term impact of the opening of ports and trading in the late Qing Dynasty on the urban commercial credit environment, taking cities above the prefecture level in the Yangtze River Delta as a sample. The study confirms that: (1) the opening of ports and commerce in the late Qing Dynasty had a significant contribution to the urban commercial credit environment, which was conducive to the transformation of production methods and interpersonal relationships from traditional to modern, and to the improvement of the urban commercial credit environment. (2) Before the signing of the Treaty of Shimonoseki, the local forces of the late Qing Dynasty were resistant to the economic aggression of the Great Powers, and the positive impact of the opening of ports and trading on the commercial credit environment of port cities was more significant, but the impact was not obvious after the signing of the Treaty of Shimonoseki. (3) From the history of the opening of ports for trade in the late Qing Dynasty, the economic aggression of the Western powers against the non-patronage areas by means of the buying class objectively strengthened the concept of rule of law and credit awareness in the local market and exerted a long-term influence on the commercial credit environment of the cities, but the impact of the opening of ports for trade on the commercial credit environment of the patronage areas was not prominent. (4) Cities located in the sphere of influence of the common law powers had a more pronounced impact on the commercial credit environment as their institutions and concepts were more easily transplanted, while the impact of the opening of ports and trading on the commercial credit environment of cities in the sphere of influence of the civil law powers was not significant. Policy Insights: (1) Enhance the ability to negotiate with foreign countries on economic and trade matters from a level-headed world perspective, and be bold and adept at fighting unreasonable rules, standards and requirements in order to better optimise the business credit environment; (2) Regulate the use of administrative resources and avoid undue administrative intervention, which is an important prerequisite for improving the basic system of the market economy to enhance the business credit environment; (3) Emphasise both connotative development to follow a Chinese style modernisation path, and (3) emphasising selective cooperation to promote outward development, promoting the interaction, convergence and matching of domestic and foreign regulations, and continuously improving the regional commercial credit environment.