To cope with climate change and achieve sustainable development, low-carbon city pilot policies have been implemented. An objective assessment of the performance of these policies facilitates not only the implementation of relevant work in pilot areas, but also the further promotion of these policies. This study uses A-share listed enterprises from 2005 to 2019 and creates a multi-period difference-in-differences model to explore the impact of low-carbon city pilot policies on corporate green technology innovation from multiple dimensions. Results show that (1) low-carbon city pilot policies stimulates the green technological innovation of enterprises as manifested in their application of green invention patents; (2) the introduction of pilot policies is highly conducive to green technological innovation in eastern cities and enterprises in high-carbon emission industries; and (3) tax incentives and government subsidies are important fiscal and taxation tools that play the role of pilot policies in low-carbon cities. By alleviating corporate financing constraints, these policies effectively promote the green technological innovation of enterprises. This study expands the research on the performance of low-carbon city pilot policies and provides data support for a follow-up implementation and promotion of policies from the micro perspective at the enterprise level.

The 14th five-year plan emphasizes the importance of marine ecology and environmental protection, and the green concept is incorporated into the high-quality development system of the marine economy. This research used the data of 11 coastal provinces and cities in China from 2006 to 2016, based on the super-efficiency slack-based measure model and global Malmquist index model. The objective was to calculate the green total factor productivity (GTFP) of the marine economy, to study the impact of the evolution of the marine industrial structure on marine economic GTFP. The study found the following: (1) in general, the upgrade of marine industrial structure promoted the growth of marine economic GTFP and presented an inverted “U” trend of initially promoting and then suppressing. Spatially, only the advancement and rationalization of industrial structure in the Yellow and Bohai Sea regions inhibited the growth of marine economic GTFP. In terms of time, the advanced marine industrial structure promoted the growth of GTFP from 2006 to 2010, whereas that of industrial structure inhibited the growth of GTFP from 2011 to 2016. (2) The GTFP of the marine economy showed an increasing trend, but the conversion rate of production technology is low. Falling into the “efficiency trap” of highly advanced technology input and low-efficiency technology output should be avoided. (3) Affected by the mismatch of regional resources or industrial structure, government intervention showed an “opposite” mechanism in areas with different marine economic strengths. Government intervention in areas with higher marine economic strength was conducive to GTFP growth, whereas government intervention in areas with weaker marine economic strength would hinder GTFP growth.

As a quasi-public product, fishery insurance has become an important starting point for the construction of the modern fishery industry chain, supply chain and value chain risk management mechanism. We used visual data processing methods and text mining technology to screen policy samples. We then built a fishery insurance policy evaluation system based on the Policy Modeling Consistency (PMC) index model. We combined the PMC index score and PMC surface to quantitatively analyze the policy samples. This paper has four important findings: (1) After three adjustments and developments, the fishery insurance policy has grown in terms of initial attention, changes, and development and gradually matured. (2) A gap exists between the content of the fishing insurance policy text and the actual demand. The scoring results of the policy samples are concentrated in the acceptable range, the policy effects are not satisfactory, and the formulation of fishery insurance policies has weak links that need to be improved. (3) The consistency and effectiveness of fishery insurance policies have developed simultaneously with fishery insurance research, and the practical effects of high-quality fishery insurance policies are conducive to the development of theoretical research. (4) The policy text of fishery insurance has major problems, such as missing joint force of issuing institutions, low professionalism of the text, inadequate subdivision guidance of fishery insurance, weak social effectiveness, high dependence on financial subsidies, lack of incentive sustainability and corresponding laws and regulations and reduction in policy feasibility among others. Considering the above issues, this paper puts forward relevant policy optimization paths and safeguard measures on the basis of giving priority to greater absolute value.

Individual aquaculture farmers in developing countries play an important role in ensuring food security. This study uses survey data from aquaculture households in Rongcheng and Xiangshan cities in China to explore the impact of cooperative participation on the benefits to the aquaculture households. The empirical results show that the participation of aquaculture farmers in cooperatives has effectively increased their net profit and output per unit area. On average, participating in cooperatives increased the net profit and output per unit area of farmers by approximately 15.55% and 11.47%, respectively. The test results of the mechanism show that the information services, technical training, and product sales guidance provided by the cooperatives have increased the net profit of the farmers. At the same time, the information services and product sales guidance provided by cooperatives are important reasons for the increase in the output per unit area.

Controversies surrounding fishery subsidy policies are widespread. Many stakeholders believe that fishery subsidies play an important role in ensuring the livelihood of fishermen. At the same time, fishery subsidies pose a threat to the stock of fishery resources and affect the sustainable development of fisheries. Based on the panel data of 30 provinces, municipalities, and autonomous regions in China from 2007 to 2017, the article empirically examines the influence of fishery subsidies on fishing. The results of the study show that China′s fishery subsidies are negatively correlated with fishing. On average, for each 1% increase in fishery subsidies, fishing will decrease by 2.9%. That is to say, in general, fishery subsidies are conducive to the sustainable development of fisheries. The results of heterogeneity analysis based on geographic location and economic development level show that fishery subsidies do not have a palpable negative influence on fishing in coastal areas or developed regions, whereas have an obvious adverse influence on fishing in inland areas or underdeveloped regions. The deterioration of the fishing environment and the natural environment explains the occurrence of this differentiation.