The coasts we live in: can there be a single definition for a coastal zone?

Abstract

Throughout the history of humankind, people have settled along seashores. The gradual accumulation of population and industrial activity in coastal areas has created preconditions for coastalisation - the movement of people and socio-economic activity to marine coasts. To date, coastal areas have a higher rate of economic development, fostering migration and an influx of capital across the globe. Scholars and policymakers voice concerns about the asymmetry of regional development and the increasing anthropogenic impact on the coastal ecosystem. It reinforces the importance of coastal zone management. In this study, we use an example of the Baltic region to identify the coastalisation patterns in the Baltic region and answer the question, whether there can be a single definition of the coastal zone of the Baltic region. According to a broad definition, the Baltic macro-region is nearly all coastal and, consequently, all settlements are influenced by the coastalisation effect. We have studied urban population dynamics in 128 cities of 45 coastal regions through the lens of various characteristics of a coastal city - the distance from the sea (10, 50, 100, and 150 km), location in a coastal region (NUTS 2), availability of a port and its primary maritime activity (tankers, cargo, fishing, passenger, recreational vessels and others). The research results suggest that despite the strong coherence of the Baltic region countries, there should not be a single delimitation approach to defining the coastal zone. Overall, the most active marine economic processes occur in the zone up to 10 km from the seacoast and 30 km from ports and port infrastructure. However, in the case of Sweden, Poland, and Latvia, the coastal zone can be extended to 50 km, and in Germany - up to 150 km inland.