Tourism index evaluation of exposed coast, Bangladesh: A modeling approach.

Over recent decades, coastal and marine tourism has significantly contributed to the degradation of coastal features and ecosystems. This study employs the Integrated Valuation of Ecosystem Services (ES) and Trade-offs (InVEST) software to assess the impact of nature-based tourism activities over 13-year periods, particularly focusing on the exposed coast of Bangladesh where most touristic activities occur. The visitation rate from the InVEST model showed a gradual increase from 2005 to 2012, followed by a decline until 2017. The western coast recorded a visitation rate ranging from 1 to 72 (low to moderate), while the eastern coast ranged between 16 and 343 (moderate to high). The real-time data of visitation rate (RTD) for the Sundarbans generally aligns with the model outputs, although occasional irregularities exist in certain years, attributed to local geomorphological inaccessibility and technological limitations. Along the central coast, the visitation rate varied from 2 to 50 (low rate) Photo-User Day (PUD) index. The findings offer valuable insights for future policymaking, facilitating the effective management of tourist sites and promoting sustainable blue economic development in this diverse and vulnerable exposed coastal zone.