Mangroves are one of the most unique ecosystems on our planet due to ability tolerate saline conditions as well as host several symbiotic relationships between the mangrove and other organisms. However, mangroves are not only an irreplaceable habitat filled with extraordinary interactions between marine and terrestrial organisms, but they also provide people with several resources and ecological services that our society is highly dependent upon.
Mangroves as Ecological Services
Mangroves have provided people with an abundance of natural resources—such as food, wood, and medicine—and ecological services—such as protecting shorelines and reducing erosion—for more than 40,000 years, and they continue to do so today. One of the most studied ecological services is the mangroves’ role as nurseries for juvenile fish; the young of over 67% of Australia’s entire commercial fish and prawn catch rely on these mangroves.
Additionally, there is a direct correlation between the extent of mangrove habitats and the size of fishery production. Mangroves are critical for sustaining fish production, providing juveniles refuge from predators, abundance of food, and shelter. Incidentally, larger habitats tended to produce more fish. However, approximately one third of the world’s mangrove habitats have been destroyed in the past 50 years due to increased human populations and the call for urban development, aquaculture, and overexploitation of resources along the coast.
Mangrove Conservation
Fortunately, mangrove habitats have finally been recognized as important marine and terrestrial environments and are protected in many national parks, reserves, and other conservation areas. However, additional awareness is needed to promote these habitats, giving the general public better understanding and appreciation of the unique salt adaptations that these organisms have undergone. Furthermore, it is in our best interest in maintaining the mangroves due to their countless ecological services that simply cannot be replaced physically or financially. According to Walton et al., the value of mangrove habitats is estimated to be approximately U.S. $9,900 per hectare, per year, covering a variety of services such as controlling erosion; protecting coastlines from floods by severe cyclones, storms, and tsunamis; providing habitats and microhabitats for a diverse array of organisms; filtering wastewater, sheltering juvenile commercial fish and prawns; natural resources such as timber (2006).
Removing mangroves result in severe impacts on the environment, such as the destruction created by Hurricane Katrina in Louisiana, United States. Lack of mangroves led to unprotected coastlines, resulting in massive flooding and coastal damage and costing billions of dollars to repair. Such devastation can be avoided with conservation and maintenance of mangrove habitats along our coastlines. Cairns, Queensland, for instance, set aside 3,600 hectares of mangrove forests as protected areas, and has since proved to be an invaluable decision. In 2006, over 11,000 vessels were sheltered within the mangroves and survived the wrath of Cyclone Larry whereas surrounding harbors and ports were left in destruction.
Such cases only demonstrate our need to protect these habitats not only for ourselves but its organisms as well. These irreplaceable habitats are one filled with extraordinary interactions and unique characteristics that are endemic to only the mangroves. Consequently, we must protect them not only in our interests, but also for the sake and survival of the thousands of organisms that call mangroves home.
References
Alongi, D. 2006. Mangrove forests: resilience, protection from tsunamis, and responses to global climate change. Estuarine, Coastal and Shelf Science Vol.76, p.1-13.
Alongi, D. M., 2002. Present state and future of the world's mangrove forests. Environmental Conservation Vol.29, p.331-49.
Duke, N. C. 2006. Australia's Mangroves: the Authoritative Guide to Australia's Mangrove Plants. St. Lucia, Qld.: University of Queensland.
Feagin, R. A., Mukherjee, N., Shanker, K., Baird, A. H., Cinner, J., et al. 2009. Shelter from the storm? Use and misuse of coastal vegetation bioshields for managing natural disasters. Conservation Letters, Vol.3, p.1–11.
Khan, M. A., and Irfan A. 2001. Salinity tolerance in some mangrove species from Pakistan. Wetlands, Ecology, and Management Vol.9 p.219-23.
Manson, F. J., Longeragan, N. R., Harch, B. D., Skilleter, G. A., and Williams, L. 2005. A broad-scale analysis of links between coastal ?sheries production and mangrove extent: a case-study for Northeastern Australia. Fisheries Research Vol.74, p.69-85.
Manson, F. J., Loneragan, N. R., Skilleter, G. A., and Phinn, S. R. 2005. An evaluation of the evidence for linkages between mangroves and fisheries: a synthesis of the literature and identification of research directions. Oceanography and Marine Biology: an Annual Review Vol.43, p.485-515.
Micheli, F. 1993. Feeding ecology of mangrove crabs in northeastern Australia: mangrove litter consumption by Sesarma messa and Sesarma smithii. Journal of Experimental Marine Biology and Ecology Vol.171, p.165-86.
Nagelkerken, I., Blaber, S., Bouillon, S., Green, P., Haywood, M., et al. 2008. The habitat function of mangroves for terrestrial and marine fauna: a review. Aquatic Botany Vol.89, 155-85.
Nerot, C., Meziane, T., Provost-Govrich, A., Rybarczyk, H., and Lee, S. Y. 2009. Role of grapsid crabs, Parasesarma erythrodactyla, in entry of mangrove leaves into an estuarine food web: a mesocosm study. Marine Biology Vol.156 p.2343-352.
Parida, A. K., and Jha, B. 2010. Salt tolerance mechanisms in mangroves: a review. Trees Vol. 24, p.199-217.
Robertson, A. I. 1986. Leaf-burying crabs: their influence on energy flow and export from mixed mangrove forests (Rhizophora spp.) in northeastern Australia. Journal of Experimental Marine Biology and Ecology Vol.102, p.237-48.
Robertson, A. I. 1991. Plant-animal interactions and the structure and function of mangrove forest ecosystems. Austral Ecology Vol.16, p.433-43.
Saenger, P. 2002. Mangrove Ecology, Silviculture, and Conservation. Dordrecht: Kluwer Academic.
Shan, L., Chao, Z. R., Sui Sui, D., and Hua, S. S. 2008. Adaptation to salinity in mangroves: implication on the evolution of salt-tolerance. Chinese Science Bulletin Vol.53, p.1708-715.
Tomlinson, P. B. 1986. The Botany of Mangroves. Cambridge Cambridgeshire: Cambridge UP.
Walton, M. E., Samonte-Tan, G. P., Primavera, J. H., Edwards-Jones, G., and Vay, L. L. 2006. Are mangroves worth replanting? The direct economic benefits of a community-based reforestation project. Environmental Conservation Vol.33 p.335-43.
Williams, M. J., Coles, R., and Primavera, J. H. 2007. A lesson from Cyclone Larry: an untold story of the success of good coast planning. Estuarine, Coastal, and Shelf Science Vol.71, p.364-367.
Join the Conversation