Implications of policy changes for coastal landscape patterns and sustainability in Eastern China

Context The capacity of a landscape to maintain multifunctionality through ongoing pressures relates to its sustainability and is affected by land use policy and environmental changes. In coastal zones, limited empirical evidence exists regarding the impact of macro-level policy changes on local landscapes and their resulting temporal and spatial responses. Objectives This paper investigates the impact of national and provincial policies on local landscape patterns in China’s Zhejiang coastal zone, encompassing human expansion and ecological restoration in terms of landscape sustainability. Methods A cluster-based landscape pattern mining is conducted from 1990 to 2020 using Google Earth Engine, which is coupled with a historical policy classification analysis. Results Coastal zone policies evolved in three stages: development-oriented (1990–2010), conservation turning (2010–2017), and land-sea coordination (2017-present). Consequently, significant temporal and spatial differences in local landscape changes are observed. Artificial surface expansion aligned with these stages, especially in Hangzhou Bay, Xiangshan Bay, and Sanmen Bay. Expansion responded more swiftly to development-stimulating policies, exhibiting longer-lasting effects. Conservation policies faced delays due to conflicting interests, varied implementation entities, unsynchronized cycles, and a lack of coordinated conservation priorities across terrestrial and marine domains. Conclusions This study provides insights into the processes and patterns of human expansion and ecological restoration in coastal zones, offering implications for coastal policies and landscape sustainability. It facilitates an evaluation of the effectiveness of coastal zone policy implementation and suggests differentiated sustainable transformation plans. Moreover, it underscores the need to strengthen coordination between sea and land development for effective coastal zone management and sustainability.