Over the last two decades, countries worldwide have become increasingly aware of the potential of marine space, which has led to a significant development in marine spatial planning (MSP) and the proliferation of studies and practical exploration of MSP issues. In China, MSP is undergoing a new series of reforms. Despite discussions in the academic community on the methods and mechanisms of MSP, issues related to planning, system designs, and implementation priorities for the next stage of MSP in China remain unresolved. This study describes the multiplan integration characterization of MSP in China. It intends to address these issues by presenting a potential MSP system and defining the specific contents and tools that need to be applied to coastal spatial planning (CSP). CSP will be at the core of MSP in China in the future.

Due to the special geographical location and unique ecosystem of islands, appropriate development and protection of islands is important for promoting the sustainable development of islands. By using the Pingtan Islands as an example, this study constructed a system of suitability evaluation indexes for marine ecological space, marine agricultural production space and marine construction space under the principle of land–sea coordination. To evaluate the spatial suitability of the sea area around islands, a GIS spatial analysis method and a hierarchical analysis method (AHP) were used, which provided useful references for the integration of land and sea and for developing islands sustainably. The research results showed that the suitability area of ecological space in the Pingtan Islands accounted for around 64.3%, the construction space accounted for around 2.1% and the agricultural production space accounted for 33.5%.

Introduction: In the future, China's mariculture must maintain its scale and improve quality. Crucial measures for achieving this goal are to optimize the layout of sea areas for aquaculture, strengthen the suitability assessment of marine aquaculture, and delineate suitable areas.Methods: This study aims to scientifically identify marine aquaculture zones suitable for marine spatial planning by constructing a comprehensive suitability assessment system, incorporating both natural and social factors. The weights of the evaluation indicators were determined using the Analytic Hierarchy Process (AHP). Taking the Lianyungang sea area as a case study, GIS technology was employed to analyze marine aquaculture suitability based on the proposed index system.Results: The results categorized the Lianyungang sea area into aquaculture zones with varying suitability levels: excellent, good, average, poor, and very poor. Based on these findings, the study further classified the area into three types of management zones: key, moderate, and limited mariculture zones.Discussion: In order to provide better decision support services and take into account the matching with Marine spatial planning and double evaluation, it is necessary to classify the evaluation results to facilitate users to propose scientific and practical management measures in this paper. Based on the evaluation results of mariculture suitability in the research area, it is necessary to strengthen the protection and development of mariculture suitable areas by providing sufficient resources and maximizing development potential.

Coastal zones play a crucial role in China's marine economy and ecological security. However, the intensification of the human activities has increased the burden on the ecosystems and carbon storage capacity of the coastal zones. In this pursuit, a case study was conducted in Lianyungang, wherein the carbon stocks were assessed using ArcGIS and InVEST model in view of the carbon neutrality targets. Remote sensing data for the years 2010, 2015, 2018, and 2020 was analyzed to assess the carbon storage capacity in the coastal zones of Lianyungang, and the causes of variation and the spatial evolution patterns were studied. The results showed that the carbon storage capacity of the coastal zones of Lianyungang showed a progressive decline with time. The carbon stock in 2020 was 6.245 × 10⁶ TC (measured by CO₂), which was more as compared to that of a decade ago. Based on estimation of the carbon stocks, several ecological restoration strategies were proposed for coastal zones of Lianyungang. The study area was divided as: ecological control space, ecological restoration space and ecological governance space. Ecological management requirements and suggestions were proposed for each type of space. Our research not only contributes to the sustainable management of coastal zones of Lianyungang, but also provides a scientific basis for achieving the carbon neutrality targets.