A Multi-Criteria Spatial Analysis of Habitat Quality and Threat Dynamics in the Mangrove Ecosystems of Puttalam Lagoon

by Jayakody J. A. S., Wijesinghe W. M. U. S.

Published: April 8, 2026 • DOI: 10.51244/IJRSI.2026.1303000136

Abstract

Puttalam Lagoon, a significant coastal ecosystem in Sri Lanka, faces multiple threats destroying its biodiversity and the crucial ecosystem services it provides to local communities. This research focuses on identifying critical Key Biodiversity Areas (KBAs) within Puttalam Lagoon, considering both threats and ecosystem services. Through a comprehensive literature review and Geographic Information System (GIS) analysis, this study examines the interplay between biodiversity, threats, and habitat quality to prioritize conservation efforts effectively. The research reveals that Puttalam Lagoon's rich biodiversity is crucial for supporting local livelihoods and maintaining ecosystem health. However, anthropogenic pressures such as pollution from agricultural runoff, sewage, and industrial waste, coupled with climate change impacts, pose significant risks to the lagoon's biodiversity and ecosystem services.
By employing methodologies like the InVEST model and the Analytic Hierarchy Process (AHP), this study identifies areas within Puttalam Lagoon that require immediate conservation attention. Regions such as Manalthivu, Mudalappaliya, Musalpitiya, Kurinjipitiya, Wannimundalama, Anawasala, and Deuch Bay are highlighted as particularly vulnerable to threats, emphasizing the need for targeted conservation interventions. Conversely, areas with higher habitat quality, offer opportunities for proactive conservation measures to safeguard their ecological integrity and maximize ecosystem service provision. The findings show that Manalthivu, Musalpitiya, Kurinjipitiya, Wannimundalama, Anawasala, and Deuch Bay need a conservation process.
In conclusion, this research provides valuable insights into the critical KBAs of Puttalam Lagoon, offering the first steps to identify the areas that require priority to be conserved and actionable policy recommendations for local governments and conservation practitioners. By prioritizing conservation efforts in vulnerable areas and enhancing ecosystem resilience, biodiversity and ecosystem services can be protected, promoting sustainable development and the well-being of people and the planet.