Hello everyone and welcome back! Now you may be wondering, what’s so special about mangroves? Why would I dedicate an entire blog to talking about them? Well my answer to that is, mangroves are simply one of the coolest ecosystems out there, serving a multitude of ecological functions that you would never expect at first glance!
Before we go into that, however, let me first clarify what exactly mangroves are. Mangroves are the unique tree or shrub species that grow in dense patches or forests “along tidal estuaries, in salt marshes, and on muddy coasts” (Britannica, 2019), but the term ‘mangrove’ also commonly refers to the above-mentioned tidal ecosystems characterized by the mangrove trees (EcoLogic Development Fund, n.d.). In my blog, I will be using the latter definition more often, as I prefer to look at mangrove ecosystems in their entirety.
Due to their intertidal nature, mangroves marry the nutrient-rich stability of the land with the dynamic flow of the tides. This allows them to serve as nurseries for many juvenile fish and crustacean species, who mature there before they enter the harsher worlds of coral reefs and the open ocean (IUCN, 2017). Mangroves provide an abundance of food in the form of bacteria, algae, plankton and mangrove tree detritus for the young species to feed on (IUCN, 2017) (Nagelkerken et al., 2008). Meanwhile, their extensive networks of characteristic prop roots serve as shelter for the juveniles against larger predators and tidal water flow, allowing them to flourish in a highly stable environment (Nagelkerken et al., 2008). As such, the IUCN asserts that mangroves are vital to “replenish some of the ocean’s fish stock” (IUCN, 2017).
Mangrove trees are also extremely resilient against changes in the environment, thus they protect coasts and shorelines from degradation by erosion (Alongi, 2008). Mangrove forests exist in harsh conditions of low oxygen, high salinity and constant exposure to wave erosion, showcasing their amazing adaptability. Furthermore, studies have highlighted their efficiency in absorbing wave energy (Alongi, 2008). I’ll be looking further into the possibility of mangroves being a viable coastal protection measure in a later post.
Finally, mangroves are in fact hugely effective carbon sinks and have tremendous potential in global carbon sequestration. Research has shown that mangrove forests are able to store more carbon per unit area than any other ecosystem on Earth, and are hence the most efficient in this aspect (Alongi, 2012). As a result, many global climate-change projects such as REDD+ and the Blue Carbon Initiative are considering mangrove restoration as a key outcome to strive towards (Alongi, 2012).
Evidently, beneath their unglamorous façades, mangroves have such great potential in maintaining ecological balances in our natural world. I personally see mangroves as a trump card in our fight against climate change and its effects, and I truly hope that mangrove restoration will take flight in Singapore in the near future. The first step towards that would be a deeper appreciation towards mangroves, so do join me next week as we continue to uncover this hidden gem of an ecosystem!
References
Alongi, D. M. (2008). Mangrove forests: Resilience, protection from tsunamis, and responses to global climate change [Review]. Estuarine, Coastal and Shelf Science, 76(1), 1-13. https://doi.org/10.1016/j.ecss.2007.08.024
Alongi, D. M. (2012). Carbon sequestration in mangrove forests [Review]. Carbon Management, 3(3), 313-322. https://doi.org/10.4155/cmt.12.20
Nagelkerken, I., Blaber, S. J. M., Bouillon, S., Green, P., Haywood, M., Kirton, L. G., Meynecke, J. O., Pawlik, J., Penrose, H. M., Sasekumar, A., & Somerfield, P. J. (2008). The habitat function of mangroves for terrestrial and marine fauna: A review [Review]. Aquatic Botany, 89(2), 155-185. https://doi.org/10.1016/j.aquabot.2007.12.007
Mangrove (2019). In Encyclopædia Britannica. Retrieved from https://www.britannica.com/plant/mangrove
EcoLogic Development Fund. (n.d.). What is a Mangrove? Retrieved September 13, 2020, from http://www.ecologic.org/actions-issues/about-the-region/what-is-a-mangrove/
IUCN. (2017, August 24). Mangroves: nurseries for the world’s seafood supply. International Union for Conservation of Nature. https://www.iucn.org/news/forests/201708/mangroves-nurseries-world%E2%80%99s-seafood-supply
Hi Marcus, this is a really interesting blog topic! I worked at Sungei Buloh for a while and the experience has definitely increased my appreciation for this ecosystem. As you mentioned earlier, mangroves are resilient and help to stabilise coastlines with their root structure. Unfortunately, protruding root structures also trap marine debris and this problem constantly plagues the mangroves. What are your thoughts on this issue and what implications do you think it holds for mangrove conservation?
Hi Sarah-Ann, thank you for your comment! You have raised a great point, our mangroves always seem to be ridden with litter. However, I would just like to point out that besides protruding root structures, I believe another major reason for the deposition of debris and litter in the mangroves is its location in an intertidal zone, where the receding tide constantly deposits trash in the area. This is an issue that plagues not just the mangroves but all coastal areas including our beaches.
That said, my view on this issue of litter-ridden coasts is that, the “fault” lies not with the mangroves and their root structures but rather with us and our anthropogenic litter. In a perfect world, this problem would not even exist as there would be no marine litter caused by people in the first place. Hence, we should not “blame” the mangroves for trapping marine debris. They are also the victims, not the perpetrators, and they deserve to be helped. Hence, I believe that this reason should not be strongly considered as an argument against mangrove conservation.
Looking at this issue from another angle, I was thinking to myself, why not turn this “disadvantage” of mangroves into a tool for us in our fight against marine litter? Since mangroves are so good at trapping marine debris, why don’t we let them do the filtering, and then we go down periodically to clear the trapped trash? I know that this idea might be pretty far-fetched, and I acknowledge the many drawbacks such as trampling, manpower etc. However, I do think that conceptually it might be worth exploring, and who knows, there might be a feasible method of implementation for this. Perhaps I’ll address this issue again in a future blog post. Once again, thank you so much Sarah-Ann for your comment, it really got me thinking 🙂