The Belt and Road Initiative (BRI) promotes a great growth of marine tourism in China. Especially when "Quanzhou - World Ocean Trade Center during Song-Yuan Dynasty of Ancient China" was included in the UNESCO World Heritage List, numerous studies have focused on marine tourism. Since blue economy is a new concept of ocean economy, the purpose of this paper is to assess future trends and challenges of marine tourism in the context of blue economy. Literature review and case study were conducted in this study. We found that (1) marine tourism based on blue economy is essential for sustainable tourism development. (2) To achieve the transformation from marine tourism to blue economy and economic growth, event and festival tourism, as well as ecotourism and cruise tourism are good approaches. However, the adoption of approaches depends on the specific natural and human environment in different locations. (3) COVID-19, Fukushima Dai-ichi Nuclear Power Plant accident, global warming, and ocean plastics are main challenges for the blue economy development of marine tourism. Thus, a comprehensive consensus on blue economy at regional and global scales among nations is crucial for overcoming difficulties. This study improves the theoretical framework of marine tourism in the context of blue economy. It also provides valuable practical insights for marine tourism development in the context of blue economy in China and other regions in the world.

From the perspective of tourism destination management, this paper briefly summarizes the important role of coastal and marine tourism in global tourism. The development of coastal and marine tourism in China falls behind and faces many challenges, but its future development is promising. In the new round of national territory development plan, we should pay attention to the special planning for the development of coastal and marine tourism. The future marine tourism development should implement the priority strategy of ecological protection. Future development trends include carrying out coastal and marine tourism research from an interdisciplinary perspective, paying attention to the investment of special funds, strengthening the environmental improvement and ecological protection of coastal and marine ecosystems, and improving the quality and humanistic environment of coastal and marine tourism for boosting the development of China's blue economy.

Island tourism is a crucial field of international tourism research. An in-depth analysis of the evolution and key areas of international island tourism research is of great significance for improving island tourism research in the context of the "maritime power" strategy and the high-quality development of the industry within dual circulation development pattern. Using the Web of Science Core Collection as data source, a visual map analysis of 1 511 papers focusing on international island from 2000 to 2019 was conducted using CiteSpace. The method was also used to reveal the development and hotspots of the research. The conclusions are as follows: (1) Island tourism research showed three different development phases since 2000: slow development phase, steady development phase, and rapid development phase. The research content has gradually shifted from focusing on the ecological environmental impact of island tourism development to the sustainable development field, which is the relationship between people and islands. (2) International island tourism research showed consumption dependence and resource dependence. Research areas and research objects mainly focused on developed countries or countries with more island resources. Among them, the three most highly cited scholars were Gossling, Hall, and Scheyvens. Most of the articles were published in three fields: environmental science and ecology, coastal ocean science, and tourism. (3) The hotspots of island tourism research included resources and environment of island tourism destinations, island tourism and global climate change, island tourism market, the economic impact of island tourism, island tourism community, consumption behavior of island tourists, island tourism planning and management, and sustainable development of island tourism. China's island tourism research should take in international island tourism research methods and results to improve theories and research methods in island tourism, and to strengthen the research on island tourism resources and environment, island sustainable tourism, economy and cultural influence, island tourists' consumption behavior and other fields.

Islands are sensitive areas where sea and land interact. Correctly handling the contradiction between human and land on islands and promoting the sustainable development of islands are the ultimate goals of the construction of ecological civilization and the implementation of national marine power strategy. Framed by vulnerability, this paper used combined weight method, set pair analysis method, and obstacle degree model to analyze the Social-Ecological System (SES) vulnerability characteristics and the evolution mechanism of its influencing factors in Changhai County from 2009 to 2018. The results are: (1) Comprehensive vulnerability and exposure followed the trend of "W" shape, sensitivity followed the trend of "M" shape, and adaptability followed the trend of "N" shape. (2) From the perspective of "exposure-sensitivity-adaptability," the analysis on the fragile structure showed that the sensitivity and adaptability of the regulation should be the focus, as well as monitoring the exposure index level. (3) Analysis of the sensitive coupling structure showed that Changhai County government should not only control the threshold of a single system, but also focus on the carrying capacity of the composite system. (4) Analysis of the adaptive control structure demonstrated that future capital investment on adaptation can be adjusted with reference to the 2012 control structure. (5) Analysis of the evolution mechanism of the key factors influencing vulnerability level showed that the continuous barrier factors of vulnerability should be strictly controlled, and the "fragility reduction" boosting factors should be developed to reduce the resistance of the "fragility reduction" barrier factors and promote the sustainable development of islands.

Compared with the mainland, islands are relatively closed. Islanders, especially young adults, tend to leave the islands in search of better life and development opportunities, as well as to solve children’s education problems. The population outflow phenomenon has become more and more severe, leading to an aging population on the islands. Most of the left-behind population on the islands is the elderly whose living needs are low, which is not beneficial to the economic development of the islands and results in the lack of vitality of the island development. Due to the attractive tourist islands’ unique tourism resources to the mainland population, a large number of tourists are attracted every summer. With the vigorous development of island tourism, tourists have added vitality to the island. This paper integrates the residence time of tourists into the time system of destination society and proposes the concept and evaluation formula of tourist population and the age of the destination society. Case study was adopted and Changhai County was selected. Based on the current situation of the island’s population vitality, this study used statistical data and questionnaire data to quantitatively analyze the impact of tourists on the island’s vitality. Results show that: (1) As a short-term population that fluctuates, tourist population has a significant impact on the vitality of the tourist destination population. It not only helps expand the population size of the destination but also temporarily changes the age structure of the destination. In addition, after tourists landing on the island, the population vitality of the island has a larger scope. (2) Social age of the destination that takes the tourist population into account is a measure of the population vitality of the tourist destination. Based on this, the influence of tourists on the population vitality of the destination can be quantitatively studied. Also, a measurable logical approach to population vitality research can be put forward. (3) On the one hand, tourists are the actual part of island population, and tourists and island residents together constitute the vitality of the island population. At the same time, the collision of individual behaviors, values, and lifestyles of off-island tourists with the local islander culture enhances the spiritual vitality of the island population. On the other hand, tourism income generated by tourists through consumption activities contributes to the construction of the island, attracting new tourists, young island residents, and migrant workers to the island, which indirectly enhances the vitality of the island population.

As a special shipping network, cruise shipping network has tourism and leisure functions in addition to traditional shipping functions, which leads to changes in its shipping network, including differences by port and network structure. Connections between ports and shipping line organization aggregate spatially, forming significant "regionalization". The Caribbean Sea is the most mature navigation area in the global cruise tourism market and cruise shipping network. Taking the Caribbean Sea as an example, this study used big data of cruise shipping trajectory and the complex network model to evaluate the centrality of cruise ports and categorized cruise port communities, analyzed regional cruise shipping network, described the port differentiation pattern and network structure, and revealed the structural and spatial rules that regional cruise shipping network followed. It is found that there were differences on functions among Caribbean cruise ports. Five types were identified: large comprehensive home port, general home port, general departure port, core port of call, and general port of call. The uneven spatial distribution of cruise ports formed a "core-periphery" spatial structure. The core was the Florida Peninsula, the secondary core was eastern Caribbean Sea, and the surrounding areas were the periphery. The shipping network of the Caribbean Sea has the characteristics of regionalization. Four port groups were formed, as well as 2 shipping channels with dense cruise shipping links, which constituted the core and skeleton of the Caribbean Sea cruise shipping network. This dual-core and multi-node structure is helpful for the construction of shipping network and may guide port construction and route organization of cruise tourism in China.

Recreational fishery is the combination of traditional fishery, tourism, and leisure industry. It is also a new branch of tourism research. Recreational fishery plays an important role in innovating the forms of tourism development and promoting the construction of the "Beautiful Countryside". This study used recreational fishery papers published in the core journals of CNKI database, CSSCI, and CSCD as data sources, and the bibliometric software CiteSpace to analyze and draw knowledge maps. Findings show that the recreational fishery research development of our country has experienced two stages: initial exploration stage and rising development stage. Multi-disciplinary participation and research framework have been basically formed. Research contents focus on the development pathway of recreational fishery. Meanwhile, the meaning of the concept, resource development and evaluation, product expression forms, developmental benefits, management, and marketing strategy of recreational fishery, are also the areas where scholars pay attention to. Finally, considering the background of leisure fishery in China, this paper put forward the following five developmental insights to the future study on fishery: constructing native theory system, incorporating research fields with national strategic policies to broaden research ideas, focusing on "people-fishing" relationship changes, investigating leisure fishery's green low carbon pattern, making the research on developmental issues as the main line.

Constructing coastal homestay inn cluster site evaluation index system is fundamental for leading the transformation and development of coastal tourism and the protection of coastal ecological environment. A total of 55 candidate indicators of assessing the coastal homestay inn cluster location were extracted from existed literature and expert interviews. Q method were used to construct a coastal homestay inn cluster location evaluation index system. This system contains six first-level indicators, including "economic environment", "tourism development", "platform conditions", "operation conditions", "geographic environment" and "support facilities", as well as 22 specific indicators. After comparing with the existing study, we found the first-level indicators for coastal homestay inn cluster location choice evaluation index system are basically the same with the ones of inland sites. Because of the fragile coastal environment and land usage conflict in coastal areas, "operating conditions" and "geographical environment" of the coastal sites weigh more than those of inland sites. Among the first-level indicators, "economic environment" weights the highest and "support facilities" weights the lowest. Among the second-level indicators, "rational plan of tourism and other industries" weights the highest while "attraction to professional talent" weights the lowest, revealing the comparative delay of coastal tourism development. This study can provide insights for coastal areas' planning on tourism development layout, location selection of homestay inn cluster, and the investing from homestay practitioners.

Grasping key factors that affect the perceived value of tourists is helpful to promote the competitiveness of tourism destinations. Taking Beihai Silver Beach National Tourism Resort in Guangxi as the research case, this study used the online reviews from Beihai Silver Beach tourists on Crip as the research sample and adopted grounded theory method to construct the influencing factor model of coastal tourists' perceived value. Five main categories and 18 corresponding categories were identified. This study also used DEMATEL model of complex system to construct the relationship matrix of the factors affecting the perceived value of coastal tourists. The key factors influencing the perceived value of coastal tourists were identified. Study found that resources and environment, management and protection, facilities and services, emotion and cost value constitute an important dimension of tourist perceived value in seaside tourism destinations. Weather conditions, beach scale, beach management and protection, tourists' pleasure, entertainment attractions, tourism infrastructure, and service are the key influencing factors of seaside tourism destination tourists' perceived value. Accordingly, some suggestions are put forward to improve the perceived value of tourists in coastal tourism destinations in China.