Analysis of the characteristics and causes of coastline variation in the Bohai Rim (1980–2010)

This paper retrieved categorical mainland coastline information in the Bohai Rim from 1980, 1990, 2000 and 2010 utilizing remote sensing and GIS technologies and analyzed the characteristics and causes of the spatial–temporal variation over the past 30 years. The results showed that during the research period, the length of the coastline of the Bohai Rim increased continuously for a total increase of 1071.3 km. The types of coastline changed significantly. The amount of artificial coastlines increased continuously and dramatically from 20.4 % in 1980 to 72.2 % in 2010, while the length of the natural coastlines decreased acutely. Areas that had coastlines that changed significantly were concentrated in Bohai Bay, the south and west bank of Laizhou Bay and the north bank of Liaodong Bay. Due to the comprehensive effects of natural and anthropogenic factors, the coastline mainly expanded seaward. Coastal engineering construction were the leading factor in coastal evolution. Furthermore, the reclamation of aquaculture pond, salt field and harbor construction were the top three construction activities. Additionally, the driving force caused coastline change showed significant temporal heterogeneity.