The marine ecological civilization construction (MECC) plays an indispensable role in the development of ecological civilization in China. With the growth of the marine economy, threats to ecological environment have been increasing. From the standpoint of land-sea coordination, this study evaluates the MECC in China's coastal province and employs social network analysis to explore the spatial correlation network structure and radiation capacity. The results show that: (1) The MECC in China's coastal provinces has exhibited a general upward trend with occasional fluctuations. However, the subsystems exhibit disparate developmental trends, with the pressure subsystem exhibiting a slight decline. (2) While the MECC of all coastal provinces has increased, the MECC of China's coastal provinces exhibits considerable variation, with each facing different development challenges. (3) The spatial correlations of the MECC among coastal provinces have become increasingly pronounced, particularly in the regions surrounding Hangzhou Bay and Bohai Bay, while long-distance trans-regional correlations are relatively weaker. (4) There have been notable improvements in the MECC radiation capacity of all provinces, most prominently in Shanghai, Zhejiang, Jiangsu, and Shandong, which currently rank among the highest in the country. Conversely, the MECC radiation capacity of Liaoning, Hebei, Fujian, and Hainan remains relatively underdeveloped. The results indicate that while the MECC has developed, it still encounters obstacles pertaining to regional disparities, subsystem challenges, and spatial correlation development. The study concludes with a series of recommendations aimed at fostering sustainable development of the MECC in China's coastal regions.

The quality risks of land trusteeship services are increasingly prominent, leading to reduced crop yields for farmers and land degradation; however, relevant research remains insufficient. This paper aims to identify and evaluate the quality risk level of land trusteeship services. It comprehensively adopts a field survey, web crawler technology, and expert consultation methods to identify quality risk types, and then uses the fuzzy comprehensive evaluation method to assess the risk level based on survey data from Chinese farmers. The main conclusions are as follows: (1) Overall, the quality risk level of land trusteeship services is at a relatively high risk level. In terms of spatio-temporal patterns, the quality risk level shows an upward trend, and the quality risk level of mid-production services is increasing at the fastest rate. There are significant variations in service quality risk across prefecture-level cities in the Shandong Province of China. (2) In terms of risk heterogeneity, the quality risk level of small-scale pure farmers is higher than that of part-time farmers and large professional farmers, in that order. The quality risk level of the “farmer + service organization” model is higher than that of the “farmer + intermediary + service organization” model. According to the order of the quality risk level of different crops, the ranking (from highest to lowest) is cash crops, wheat, and corn. (3) The high quality risks of land trusteeship services will impact the multifunctionality of land systems. It exacerbates the land pollution and fertility degradation because of excessive application of chemical inputs like pesticides, fertilizers, and mulch by service organizations. It consequently destroys ecological systems, hinders sustainable agricultural development, and impacts farmers’ income and national food security by reducing yields. The research findings contribute to controlling the quality risks of land trusteeship services and protecting land.

The service quality of land trusteeship is often subpar due to farmers’ ineffective supervision of service providers’ opportunistic behaviors. However, the existing literature has not given much attention to this agency issue from the principal–agent theory. Accordingly, this paper analyzes the mechanism of supervision failure leading to the quality risk of land trusteeship services, then applies the IV-Heckman model to empirically test the impact with follow-up survey data of 1138 farmers in China. The study found that: (1) supervision failure has a positive impact on the quality risk of land trusteeship services. The OLS model overestimated the main effect of supervision failure by 23%, while the Heckman model effectively corrected the sample selectivity bias. (2) The results of heterogeneity analysis showed that the effect of supervision failure on the quality risk of different crop types is in the order of cash crops, corn, and wheat. The impact of supervision failure on quality risk in different links is single-link, multi-link, and full-link in that order. (3) The quantile regression shows that the higher the level of quality risk is, the deeper the impact of supervision failure on the quality risk of land trusteeship services is. Accordingly, this paper proposes the following policy insights. First, a sound regulatory mechanism for land trusteeship services should be established. Second, increase the punishment for land trusteeship services violations. Third, establish a digital supervision platform to supervise and evaluate the service process and quality.

In the context of gradual enhancement of land trusteeship service quality risk, the existing literature has not provided a reasonable answer about the risk reduction role of interests linkage mechanism. Based on the collection of farmers’ data from Shandong province of China, this study applies the propensity score matching (PSM) and instrumental variable model to analyze the impact of interests linkage mechanism on the quality risk of land trusteeship services. It is found that (1) the interests linkage mechanism has a significant negative impact on the quality risk of land trusteeship services. This finding still holds after a series of robustness tests. The risk-reducing effect of the interests linkage mechanism was overestimated before the sample matching treatment. (2) The reduction effect of service quality risk in the med-production is greater than that of pre-production and post-production service quality risk in that order. (3) Small-scale service providers are more likely to pose quality risk, while establishing interests linkage mechanism has the most significant effect on reducing quality risk among part-time farmers. This study findings help to enrich the theory of interests linkage mechanism between farmers and service organizations, which also can provide practical guidance for the prevention and control of land trusteeship service quality risk.