Figure 3

Negombo lagoon – Permanently open, locationally stable inlet: Type 1 (left), Kalutara lagoon – Permanently open, alongshore migrating inlet: Type 2 (middle), Maha Oya river – Seasonally/Intermittently open, locationally stable inlet: Type 3 (right). The red dotted circles indicate inlet location (Reproduced from Duong et al.24, all rights reserved).