Regulating services of mangroves

The regulating services provided by mangrove forests are extensive.  Some important ES include carbon sequestration, coastal protection, and flood and erosion control. Firstly, carbon sequestration and burial refers to the absorption of carbon from the atmosphere and its retention in underground storage.[1][2] In 2015, according to Alongi and Mukhopadhyay, mangrove forests occupy 2% of the world’s coastline and are responsible for approximately 30% of carbon burial in tropical and sub tropical continental borders.[3] This carbon sequestration and burial process is considered important to mitigate the impacts of climate change.[4] Mangroves forests are highly productive, carbon rich ecosystems and compared to terrestrial forests they have a greater ratio of below to above ground carbon storage.[4]

Mangrove forests provide various levels of coastal protection from storm surges, tsunamis, erosion, strong winds and wave action. Firstly, storm surges occur when increased winds and low pressure from tropical storms (hurricanes, cyclones and typhoons) steadily raise the sea level above normal tidal levels.[5][6] Mangrove forests attenuate storm surges and waves directly and indirectly. Directly, the trunks, leaves, root network and pneumatophores weaken the water velocity and turbulence.[6][7][8] While indirectly, with their root networks mangroves provide stabilisation and development of the coastal soil.[6][9] In 2008, according to Das and Vincent, in a study of 409 villages in India that were affected by a powerful cyclone in October 1999 it was found that villages with greater widths of mangrove forests to the coastline recorded much fewer deaths as compared to villages that had little to no mangroves. [10]

Tsunamis are natural hazards that occur when underground earthquakes and volcanoes result in multiple large waves that displace large quantities of sea water.[6] Mangrove forests offer some limited protection against tsunamis. The level of protection is dependent on other variables such as mangrove forest type, density, stem and root size and invariably the magnitude of the tsunami itself.[9] Modelled output for a 100 metre wide forest showed an approximate 90% decrease in the tsunami flow pressure. This study was simulated on the 1998 Papa New Guinea tsunami.[9][11] However, in 2011 Laso Bayas et al., cautioned on the over reliance on mangrove forests for protection from tsunamis, this study found that mangrove forests offered limited protection. In the 2004 Indian Ocean Tsunami that affected Indonesia casualties were reduced at settlements behind mangrove forests by 8% but structural damage remained.[12]

Despite the benefits gained in mitigating natural hazards it is important to note that the extent of coastal protection will vary in scenarios where initial impact by multiple wave tsunamis and storm surges damage and deplete the mangrove forests protective ability.[13] Therefore, less protection capability to multiple and frequent future waves from tsunamis and surges is possible.[6] Mangrove forests are indeed valuable ecosystems, but in considering their protection from tsunamis and storm surges there are many exogenous factors that have an important role.[14] Factors such as topography, elevation, other marine seascape factors like coral reefs and seagrass beds also contribute to natural hazard mitigation.[6]

Thirdly, coastal erosion that also occurs due to wave action is influenced by mangrove forests. The complex root system of many mangrove species contributes to strengthening the soil and increases sediment build up.[15][16] Organic matter is added from leaf litter and the roots which can elevate the soil profile and reduce erosion thus encouraging a stabilisation effect of the soil.[9] As a result mangrove forests have expanded coastlines from the accumulation of sediment and organic matter combined with reduced erosion.[6][17] A correlation was observed between mangrove plant structure and coastal erosion where deforested coastlines exhibited similar levels of erosion as coastlines where mangroves were not part of the seascape.[7] Flood control is another important regulating service of mangrove forests.

Flood and water flow control is a regulating service with indirect use value provided by mangrove forests.[18] In 1998, according to Ewel et al., basin mangrove forests may provide protection from episodic floods by providing greater storage capacity for runoff.[19] Flooding may occur due to storm surges, tidal changes and torrential rainfall. The risk of storm surge flood occurrence is exacerbated in low lying areas which often coincide with development and infrastructure.[20]  Expansive and wide mangrove forests contribute to significant flooding reduction in flood prone areas due to the root structure that assists with sedimentation.[5][21] Furthermore, in instances of flooding mangrove forests has notably reduced the organic matter leading to water purification and quality improvements.[22]

Mangrove forests are recognised for their benefits in treating water from flooding, wastewater from aquaculture and sewage resulting from increased development.[23] Mangrove forests efficiently process wastewater pollutants from pre-treated secondary sewage from domestic waste through tidal flushing, mangrove plant uptake and microbial metabolic functions in the sediment.  Furthermore, it was determined that mangrove-aquaculture coupling systems are effective in treating aquaculture wastewater.[23]

Cultural services of mangroves

The cultural services utilised from mangrove forests are due to the unique landscape and diversity in flora and fauna.[24] Firstly, tourism is major service that can be gained from mangrove forests. In 2013, according to Uddin et al., tourism increased over the years at the Sundarban reserve due to increased investment into facilities improvements by the Forestry Department (FD) and private tour operators increasing revenue for the FD.[25] A subset of tourism known as eco-tourism is another considerable opportunity from mangrove forested sites.  Ecotourism refers to where little to zero negative impacts occur on the environment it is non-damaging, non-degrading and sustainable in approach and it considers the primary motive to participate is the enjoyment of nature.[26] Ecotourism and bird watching are considered a benefit of mangrove forested sites.[27]

Another cultural service at mangrove forests sites that can be found in many forms is recreation. In 2012, according to van Ripper et al., at the Hinchinbrook National Park, Australia mangrove sites are used for recreational fishing in the estuaries. Furthermore the area is used for sea kayaking, snorkelling, diving, traditional hunting and spear fishing.[28] The natural aesthetics of these forests are also important for both tourism and recreation. Undisturbed mangrove forested sites are attractive to tourists and communities. The development of trails and boardwalks are noted as an opportunity to generate income from land that may otherwise be undeveloped.[19] In some cases such as the Pacific islands in addition to the natural aesthetic benefits, mangrove stands may reside on land that has a customary value to local communities.[29]  Customary values can encompass traditional and spiritual uses such as Rusha Mela and Bano bibi as observed by the Hindu communities at the Sundarbans.[25]

Finally, education and research is another significant cultural service of mangrove forests. [30]There are many instances of education and research programmes by research institutions and universities for the Sundarbans.[25] Also, research is done worldwide such as the work by our very own Mangles group, investigating the mangrove areas from the east at Thailand and Sri Lanka to the west in the Caribbean.


Photo Credit: Angie Elwin taken in Trat, Thailand

[1] Donato, D., Kauffman, J., Murdiyarso, D., Kurnianto, S., Stidham, M. and Kanninen, M. (2011). Mangroves among the most carbon-rich forests in the tropics. Nature Geoscience, 4(5), pp.293-297.

[2] Locatelli, T., Binet, T., Kairo, J., King, L., Madden, S., Patenaude, G., Upton, C. and Huxham, M. (2014). Turning the Tide: How Blue Carbon and Payments for Ecosystem Services (PES) Might Help Save Mangrove Forests. AMBIO, 43(8), pp.981-995.

[3] Alongi, D. and Mukhopadhyay, S. (2015). Contribution of mangroves to coastal carbon cycling in low latitude seas. Agricultural and Forest Meteorology, 213, pp.266-272.

[4] Alongi, D. (2012). Carbon sequestration in mangrove forests. Carbon Management, 3(3), pp.313-322.

[5] Spalding, M., Ruffo, S., Lacambra, C., Meliane, I., Hale, L., Shepard, C. and Beck, M. (2014b). The role of ecosystems in coastal protection: Adapting to climate change and coastal hazards. Ocean & Coastal Management, 90, pp.50-57.

[6] Marois, D., and Mitsch, W.J. (2015). Coastal protection from tsunamis and cyclones provided by mangrove wetlands – a review. IntJ Biodivers Sci, Ecosyst Serv Manag. 11:70–82.

[7] Gedan, K., Kirwan, M., Wolanski, E., Barbier, E. and Silliman, B. (2010). The present and future role of coastal wetland vegetation in protecting shorelines: answering recent challenges to the paradigm. Climatic Change, 106(1), pp.7-29.

[8] Mazda, Y., Magi, M., Ikeda, Y., Kurokawa, T. and Asano, T. (2006). Wave reduction in a mangrove forest dominated by Sonneratia sp. Wetlands Ecology and Management, 14(4), pp.365-378.

[9] Alongi, D. (2008). Mangrove forests: Resilience, protection from tsunamis, and responses to global climate change. Estuarine, Coastal and Shelf Science, 76(1), pp.1-13.

[10] Das, S. and Vincent, J. (2009). Mangroves protected villages and reduced death toll during Indian super cyclone. Proceedings of the National Academy of Sciences, 106(18), pp.7357-7360.

[11] Hiraishi, T., Harada, K., 2003. Greenbelt tsunami prevention in South Pacific region. Report of the Port and Airport Research Institute 42, 1e23. Available from:

[12] Laso Bayas, J., Marohn, C., Dercon, G., Dewi, S., Piepho, H., Joshi, L., van Noordwijk, M. and Cadisch, G. (2011). Influence of coastal vegetation on the 2004 tsunami wave impact in west Aceh. Proceedings of the National Academy of Sciences, 108(46), pp.18612-18617.

[13] Kerr, A., Baird, A. and Campbell, S. (2006). Comments on “Coastal mangrove forests mitigated tsunami” by K. Kathiresan and N. Rajendran [Estuar. Coast. Shelf Sci. 65 (2005) 601–606]. Estuarine, Coastal and Shelf Science, 67(3), pp.539-541.

[14] Kerr, A. and Baird, A. (2007). Natural Barriers to Natural Disasters. BioScience, 57(2), pp.102-103.

[15] Mazda, Y., Magi, M., Kogo, M. and Nguyen Hong, P. (1997). Mangroves as a coastal protection from waves in the Tong King delta, Vietnam. Mangroves and Salt Marshes, 1(2), pp.127-135.

[16] Kathiresan, K.. (2003). How do mangrove forests induce sedimentation?. Revista de Biología Tropical51(2), 355-360.

[17] Thampanya, U., Vermaat, J., Sinsakul, S. and Panapitukkul, N. (2006). Coastal erosion and mangrove progradation of Southern Thailand. Estuarine, Coastal and Shelf Science, 68(1-2), pp.75-85.

[18] Dencer-Brown, A., Alfaro, A., Milne, S. and Perrott, J. (2018). A Review on Biodiversity, Ecosystem Services, and Perceptions of New Zealand’s Mangroves: Can We Make Informed Decisions about Their Removal?. Resources, 7(1), p.23.

[19] Ewel, K., Twilley, R. and Ong, J. (1998). Different Kinds of Mangrove Forests Provide Different Goods and Services. Global Ecology and Biogeography Letters, 7(1), p.83.

[20] Spalding M, McIvor A, Tonneijck FH, Tol S and van Eijk P (2014a) Mangroves for coastal defence. Guidelines for coastal managers & policy makers. Published by Wetlands International and The Nature Conservancy. 42 p

[21] Kathiresan, K. (2010). Importance of mangrove forests of India. Journal of Coastal Management, 1(1), pp.11-26.

[22] Wang, M., Zhang, J., Tu, Z., Gao, X. and Wang, W. (2010). Maintenance of estuarine water quality by mangroves occurs during flood periods: A case study of a subtropical mangrove wetland. Marine Pollution Bulletin, 60(11), pp.2154-2160.

[23] Ouyang, X. and Guo, F. (2016). Paradigms of mangroves in treatment of anthropogenic wastewater pollution. Science of The Total Environment, 544, pp.971-979.

[24] Barbier, E., Hacker, S., Kennedy, C., Koch, E., Stier, A. and Silliman, B. (2011). The value of estuarine and coastal ecosystem services. Ecological Monographs, 81(2), pp.169-193.

[25] Uddin, M., de Ruyter van Steveninck, E., Stuip, M. and Shah, M. (2013). Economic valuation of provisioning and cultural services of a protected mangrove ecosystem: A case study on Sundarbans Reserve Forest, Bangladesh. Ecosystem Services, 5, pp.88-93.

[26] Valentine, P. (1993). Ecotourism and nature conservation. Tourism Management, 14(2), pp.107-115.

[27] Mitsch, W., Bernal, B. and Hernandez, M. (2015). Ecosystem services of wetlands. International Journal of Biodiversity Science, Ecosystem Services & Management, 11(1), pp.1-4.

[28] van Riper, C., Kyle, G., Sutton, S., Barnes, M. and Sherrouse, B. (2012). Mapping outdoor recreationists’ perceived social values for ecosystem services at Hinchinbrook Island National Park, Australia. Applied Geography, 35(1-2), pp.164-173.

[29] Lal, P. (2003). Economic valuation of mangroves and decision-making in the Pacific. Ocean & Coastal Management, 46(9-10), pp.823-844.

[30] Friess, D. (2016). Ecosystem Services and Disservices of Mangrove Forests: Insights from Historical Colonial Observations. Forests, 7(12), p.183.