A REVIEW ON ECOLOGICAL SIGNIFICANCE OF WETLANDS FOR BIODIVERSITY CONSERVATION IN SRI LANKA
DOI:
https://doi.org/10.17501/27059901.2026.4101Keywords:
biodiversity conservation, carbon sequestration, ecosystem services, urban wetlands, nature-based solutionsAbstract
Wetlands are considered as one of the most productive ecosystems in the world, playing a vital role in biodiversity conservation. Providing critical ecosystem services, they effectively contribute to enhancing environmental stability. This study provides a comprehensive review of the ecological significance of wetlands in Sri Lanka, with a particular focus on urban wetland systems. A systematic literature-based qualitative review approach was adopted to synthesize relevant peer-reviewed research papers, journal articles, books and publications by recognized government and non- government organizations. The analysis is guided by the Millennium Ecosystem Assessment framework (MEA), Nature-Based Solutions framework (NbS) and perspective and Social-ecological systems thinking approach (SES). The key findings highlight that, wetlands support biodiversity conservation and environmental management by providing a range of ecosystem services including flood mitigation, carbon sequestration, habitat provision, water purification and coastal erosion control. However, their effectiveness is highly context-dependent. In urban environments such as Colombo, the impacts of land-use pressure, pollution and fragmentation on ecosystem functionality are significantly higher, as they reduce the consistency of ecosystem service provision. This study highlights the importance of integrating wetland technology in urban infrastructure as nature-based solutions to enhance resilience against natural disasters and biodiversity conservation. However, these invaluable ecosystems are gradually declining due to various natural and anthropogenic factors. Among these, anthropogenic factors including rapid urbanization, agricultural expansion, illegal land encroachments, overexploitation of natural resources and ecotourism exert significant pressure on wetland degradation. The study emphasizes the need for integrated wetland management and urban ecological planning to enhance biodiversity conservation and environmental resilience.
Downloads
References
Alongi, D. M. (2008). Mangrove forests: Resilience, protection from tsunamis, and responses to global climate change. Estuarine, Coastal and Shelf Science, 76(1), 1–13. https://doi.org/10.1016/j.ecss.2007.08.024
Athukorala, D., Estoque, R. C., Murayama, Y., & Matsushita, B. (2021). Impacts of Urbanization on the Muthurajawela Marsh and Negombo Lagoon, Sri Lanka: Implications for Landscape Planning towards a Sustainable Urban Wetland Ecosystem. Remote Sensing, 13(2), 316. https://doi.org/10.3390/rs13020316
Bansal, S., Tangen, B., & Finocchiaro, R. (2016). Temperature and Hydrology Affect Methane Emissions from Prairie Pothole Wetlands. Wetlands, 36(S2), 371–381. https://doi.org/10.1007/s13157-016-0826-8
Barbier, E. B., Hacker, S. D., Kennedy, C., Koch, E. W., Stier, A. C., & Silliman, B. R. (2011). The value of estuarine and coastal ecosystem services. Ecological Monographs, 81(2), 169–193. https://doi.org/10.1890/10-1510.1
Barman, A., Rajak, F., & Jha, R. (2024). Integrating Wetlands as Nature-Based Solutions for Sustainable Built Environments: A Comprehensive Review. Engineering, Technology & Applied Science Research, 14(6), 18670–18680. https://doi.org/10.48084/etasr.8923
Brock, M. A., Smith, R. G. B., & Jarman, P. J. (1999). Drain it, dam it: Alteration of water regime in shallow wetlands on the New England Tableland of New South Wales, Australia. Wetlands Ecology and Management, 7(1–2), 37–46. https://doi.org/10.1023/A:1008416925403
Dayananda, L. P. D. (2004). Enhancing sustainable livelihoods: A case study from Wanathavilluwa, Sri Lanka. IUCN, Sri Lanka.
Dayathilake, D. D. T. L., Lokupitiya, E., & Wijeratne, V. P. I. S. (2021). Estimation of Soil Carbon Stocks of Urban Freshwater Wetlands in the Colombo Ramsar Wetland City and their Potential Role in Climate Change Mitigation. Wetlands, 41(2), 29. https://doi.org/10.1007/s13157-021-01424-7
Duarte, C. M., Losada, I. J., Hendriks, I. E., Mazarrasa, I., & Marbà, N. (2013). The role of coastal plant communities for climate change mitigation and adaptation. Nature Climate Change, 3(11), 961–968. https://doi.org/10.1038/nclimate1970
Edirisooriya, E. M. N. T., Neluwala, N. G. P. B., & Weerakoon, W. M. S. B. (2022). Flood Inundation Modelling in Greater Colombo Region Using HEC-RAS 2D. Engineer: Journal of the Institution of Engineers, Sri Lanka, 55(3), 21. https://doi.org/10.4038/engineer.v55i3.7518
Everard, M. (2020). Managing socio-ecological systems: Who, what and how much? The case of the Banas River, Rajasthan, India. Current Opinion in Environmental Sustainability, 44, 16–25. https://doi.org/10.1016/j.cosust.2020.03.004
Garba, S. I., Ebmeier, S. K., Bastin, J.-F., Mollicone, D., & Holden, J. (2025). Wetland fragmentation associated with large populations across Africa. Nature Communications, 16(1), 5065. https://doi.org/10.1038/s41467-025-59373-2
Haase, D. (2017). Urban Wetlands and Riparian Forests as a Nature-Based Solution for Climate Change Adaptation in Cities and Their Surroundings. In N. Kabisch, H. Korn, J. Stadler, & A. Bonn (Eds), Nature-Based Solutions to Climate Change Adaptation in Urban Areas (pp. 111–121). Springer International Publishing. https://doi.org/10.1007/978-3-319-56091-5_7
Hails, A. J. (Ed.). (1996). Wetlands, biodiversity and the Ramsar convention: The role of the convention on Wetlands in the conservation and wise use of biodiversity. Ramsar Convention Bureau.
Hettiarachchi, M., Morrison, T. H., Wickramsinghe, D., Mapa, R., De Alwis, A., & McAlpine, C. A. (2014). The eco-social transformation of urban wetlands: A case study of Colombo, Sri Lanka. Landscape and Urban Planning, 132, 55–68. https://doi.org/10.1016/j.landurbplan.2014.08.006
Huq, Md. E., Shoeb, A. Z. M., Hossain, M. A., Fahad, S., Kamruzzaman, M. M., Javed, A., Saleem, N., Adnan, K. M. M., Sarker, S. A., Ali, M. Y., & Sarven, Most. S. (2020). Measuring Vulnerability to Environmental Hazards: Qualitative to Quantitative. In S. Fahad, M. Hasanuzzaman, M. Alam, H. Ullah, M. Saeed, I. Ali Khan, & M. Adnan (Eds.), Environment, Climate, Plant and Vegetation Growth (pp. 421–452). Springer International Publishing. https://doi.org/10.1007/978-3-030-49732-3_17
International Union for Conservation of Nature Sri Lanka. (2004). Wetland conservation in Sri Lanka: Proceedings of the National Symposium on Wetland Conservation and Management: June 19th and 20th, 2003, IUCN-The World Conservation Union, Sri Lanka Country Office. IUCN, Sri Lanka. National Symposium on Wetland Conservation and Management.
International Water Management Insitute. (2024). Urban wetlands and the built environment: How Colombo’s green spaces enhance city life [Research institute website]. International Water Management Insitute. Retrieved from https://www.iwmi.org/news/colombo-wetlands-and-the-built-environment/
Janashantha, N. P. A. S., Rathnayake, W. A. S. P. P., & Priyadarshana, P. H. M. G. C. (2023). Biodiversity and importance of urban wildlife in wetland city Colombo, Sri Lanka: A literature review. Citizen Scientists’ Symposium on Conservation and Ecology. Retrieved from https://www.researchgate.net/publication/369037769_Biodiversity_and_importance_of_urban_wildlife_in_wetland_city_Colombo_Sri_Lanka_a_literature_review
Kačergytė, I., Arlt, D., Berg, Å., Żmihorski, M., Knape, J., Rosin, Z. M., & Pärt, T. (2021). Evaluating created wetlands for bird diversity and reproductive success. Biological Conservation, 257, 109084. https://doi.org/10.1016/j.biocon.2021.109084
Li, D., Peng, Z., Liu, G., & Wei, C. (2023). Flow Structures in Open Channels with Emergent Rigid Vegetation: A Review. Water, 15(23), 4121. https://doi.org/10.3390/w15234121
Li, L., Xu, H., Zhang, Q., Zhan, Z., Liang, X., & Xing, J. (2024). Estimation methods of wetland carbon sink and factors influencing wetland carbon cycle: A review. Carbon Research, 3(1), 50. https://doi.org/10.1007/s44246-024-00135-y
Marambanyika, T., Mupfiga, U. N., Musasa, T., & Ngwenya, K. (2021). Local Perceptions on the Impact of Drought on Wetland Ecosystem Services and Associated Household Livelihood Benefits: The Case of the Driefontein Ramsar Site in Zimbabwe. Land, 10(6), 587. https://doi.org/10.3390/land10060587
Mcleod, E., Chmura, G. L., Bouillon, S., Salm, R., Björk, M., Duarte, C. M., Lovelock, C. E., Schlesinger, W. H., & Silliman, B. R. (2011). A blueprint for blue carbon: Toward an improved understanding of the role of vegetated coastal habitats in sequestering CO2. Frontiers in Ecology and the Environment, 9(10), 552–560. https://doi.org/10.1890/110004
Mitsch, W. J., Bernal, B., & Hernandez, M. E. (2015). Ecosystem services of wetlands. International Journal of Biodiversity Science, Ecosystem Services & Management, 11(1), 1–4. https://doi.org/10.1080/21513732.2015.1006250
Mitsch, W. J., Bernal, B., Nahlik, A. M., Mander, Ü., Zhang, L., Anderson, C. J., Jørgensen, S. E., & Brix, H. (2013). Wetlands, carbon, and climate change. Landscape Ecology, 28(4), 583–597. https://doi.org/10.1007/s10980-012-9758-8
Nag, S. K., Das Ghosh, B., Nandy, S., Aftabuddin, M., Sarkar, U. K., & Das, B. K. (2023). Comparative assessment of carbon sequestration potential of different types of wetlands in lower Gangetic basin of West Bengal, India. Environmental Monitoring and Assessment, 195(1), 154. https://doi.org/10.1007/s10661-022-10729-x
Pouyat, R. V. (2020). Forest and Rangeland Soils of the United States Under Changing Conditions: A Comprehensive Science Synthesis (D. S. Page-Dumroese, T. Patel-Weynand, & L. H. Geiser, Eds). Springer Nature.
Rawal, P., Laaksonen, T., Kačergytė, I., Seimola, T., Väänänen, V.-M., & Lindén, A. (2026). Designing for diversity: Wetland ageing and habitat features at multiple scales influence the use of constructed wetlands by breeding waterfowl. Biological Conservation, 314, 111669. https://doi.org/10.1016/j.biocon.2025.111669
Sahrawat, K. L. (2003). Organic matter accumulation in submerged soils. In Advances in Agronomy (Vol. 81, pp. 169–201). Elsevier. https://doi.org/10.1016/S0065-2113(03)81004-0
Tangen, B. A., & Bansal, S. (2020). Soil organic carbon stocks and sequestration rates of inland, freshwater wetlands: Sources of variability and uncertainty. Science of The Total Environment, 749, 141444. https://doi.org/10.1016/j.scitotenv.2020.141444
World Conservation Union Sri Lanka, Central Environmental Authority, & International Water Management Institute. (2006). National wetland directory of Sri Lanka.
Were, D., Kansiime, F., Fetahi, T., Cooper, A., & Jjuuko, C. (2019). Carbon Sequestration by Wetlands: A Critical Review of Enhancement Measures for Climate Change Mitigation. Earth Systems and Environment, 3(2), 327–340. https://doi.org/10.1007/s41748-019-00094-0
Wu, Y., Sun, J., Hu, B., Zhang, G., & Rousseau, A. N. (2023). Wetland-based solutions against extreme flood and severe drought: Efficiency evaluation of risk mitigation. Climate Risk Management, 40, 100505. https://doi.org/10.1016/j.crm.2023.100505
Wu, Y., Xi, Y., Feng, M., & Peng, S. (2021). Wetlands Cool Land Surface Temperature in Tropical Regions but Warm in Boreal Regions. Remote Sensing, 13(8), 1439. https://doi.org/10.3390/rs13081439
Yoezer, D., Hall, A., Horta, A., & Wassens, S. (2026). Conservation status and threats to freshwater forested wetlands: A global systematic review. Biological Conservation, 315, 111704. https://doi.org/10.1016/j.biocon.2026.111704
Downloads
Published
Issue
Section
License
Copyright (c) 2026 Tharushi Poornima
This work is licensed under a Creative Commons Attribution 4.0 International License.
