Pan, Y.; Deng, J.-S.; Cai, J.; Wang, K.; Wu, C.; Li, J., and Li, J., 2015. Spatiotemporal dynamics of island land expansion response to intensive island development and reclamation.Along with the numerous benefits of rapid reclamation and economic advancement in islands, the intensified conflict between island development and ecosystem sustainability should arouse concern worldwide. The islands in Zhejiang, China, have been an outstanding center of marine economic development but also among the areas most threatened by human activities in recent years. This study aimed to investigate the historical impacts of development and reclamation on the islands' land expansion and morphology change from the 1970s to 2013 and to identify the strongest signals of land transitions among the expanded areas. The results indicated that the islands dramatically expanded during 2000–13, with a threefold area increase compared to the first 30 years of the study period, and that the coastlines geometries became simpler with strong decreases in fractal dimension. More than 50% of the additional land was occupied by artificial structures that substantially altered the physical environment. These changes were mostly concentrated on the three island types: comprehensive, port and industry, and tourism. They are mainly the outcome of the spatial co-occurrence of port, logistics, and coastal industries or tourism establishments in response to government plans; moreover, the alteration of economic patterns presents as an aggravating force. Historically, the extensive islands' land expansion for coastal activities has brought about economic prosperity, but it has done so at the expense of environmental degradation, which highlighted the implications for guiding sustainable island development, particularly under the background of current economic booms in maritime China.