Climate change is affecting nearly all biomes on the planet. The degradation and deforestation of mangroves, seagrass beds and tidal marshes in particular could release up to a billion tonnes of carbon dioxide annually if something is not done soon (Pendleton et al, 2012). Some financiers, scientists and non-governmental organizations (NGOs) believe that conservation through carbon credit generation and sales (i.e. markets), is the answer.

Carbon credits are a marker driven mitigation initiative which encompasses the production and sale of carbon credits, in what is known as the carbon credit market. A carbon credit represents a tonne of carbon dioxide released into the atmosphere and the idea is, that if an entity releases 1 tonne of carbon dioxide, purchasing or creating a carbon credit (for their own use) will cancel out their emissions.

The largest carbon credit trading forum is the EU Emissions Trading Scheme (EU ETS), an example of a compliance market, meaning that credits being processed are used by companies who are legally mandated to reduce their emissions (such as those in the EU). The EU ETS accepts credits generated from projects which have shown to reduce net emissions. An example would be a Clean Development Mechanism (CDM) project where an industrial company from the UK has built solar panels in India for a village, reducing the dependency on coal and consequently reducing the emissions by a certain amount per year.

There also exists a global voluntary market for carbon credits. The voluntary market is still in its infancy and is a refuge for those credits which do not meet the EU ETS credit prerequisites. Credit prices are affected by a lot of factors so if a company is able to create a lot of them from a particularly carbon rich site they may be able to increase the value of the credit if that site also has endangered species on it, hence the other term, corporate social responsibility (CSR) credits. The credits that fit into CSR/voluntary markets are often those from forest projects which come under the umbrella of UN REDD credits (United Nations Reducing Emissions from Deforestation and Forest Degradation) or IFM (Improved Forest Management). UN REDD has been in existence since the United Nation’s Framework Convention on Climate Change’s Kyoto Protocol. It is under UN REDD where new mangrove and seagrass bed conservation projects may appear in the coming years and that is where things get interesting for the marine science and conservation community.

The success of REDD forest projects relies heavily on the ability of the project to conserve forests and to avoid degradation and deforestation. The regrowth of the forest amasses carbon in the wood and roots and it is this sequestration that allows carbon credits to be formed. In short, as the forest grows, CO2 is locked away for good or until the tree dies in several hundred years or so. It is this combination of offsets (avoided emissions from not cutting the forest) and sequestration that can be converted into carbon credits. The project must prove that without its presence, the forests would surely be cut down, something called additionality, and without it a project is void. The basic concept is that deforestation must be avoided in order to keep the project viable environmentally and financially.

Mangroves below the surface. Image: Jason Flower.

Mangroves above the surface. Image: Jason Flower.

Zanzibar has many seagrass beds including those in the rural peninsula of Fumba. Image: Melissa Schiele.

This model is being developed in order for mangroves and seagrass beds to be conserved in a potentially more economically viable manner. It may soon be the case that investors begin to plough money into the companies which are doing these projects specifically for mangroves and seagrass beds and not just forests, as mangroves hold more carbon and thus generate more credits that can be sold. Countries where this could happen first are Indonesia and Brazil, which have the largest extent of mangroves in the world.

Mangroves, seagrass beds and wetlands are delicate and diverse ecosystems which are often subject to exploitation by local people for wood collection to aquaculture. They are at risk from rising sea levels but could also play an important role in climate change mitigation as carbon storage facilities. The ecosystem service of carbon storage is now being recognized by large NGOs and governments and much frantic research is going into clarifying the carbon sequestration rates of these coastal ecosystems and consequently, monetization mechanisms are being created. With mangrove deforestation being three times more detrimental for the environment than regular deforestation, it is unsurprising that carbon credit generators are trying to find ways of capitalizing on them. Deforestation (including coastal system destruction) accounts for 8–20% of total global emissions. It is also important to realize that mangroves on average store at least twice as much carbon than most tropical rainforests, with certain sites in Micronesia (for example) holding around 70% of their carbon in the soils. Mangroves, seagrass beds or salt marshes are found on nearly all non-Arctic or Antarctic coastlines in some form and their carbon benefits are augmented by the biodiversity benefits and amenities that come with conserving such places, not least being protection against storms. NGOs and local governments in developing nations face a difficult challenge in conservation of coastal environments due to often poor funding and limited staff coupled to increasing populations. Paper parks (and Marine Protected Areas MPAs) can also be a hindrance to conservation efforts.

As well as storing carbon, seagrass beds (left) are home to a diverse flora and fauna. Image: Melissa Schiele.

Sea cucumber, Fumba, Zanzibar (right). Image: Melissa Schiele.

The effectiveness of the REDD projects varies greatly, however. Only a handful of projects have generated credits which have been Environment & Conservation validated by the Verified Carbon Standard (VCS). A REDD project has a lot of moving parts and as the industry is relatively new, many carbon credit companies are still trying to figure out how to monetize and even create the credits under the strict policy guidelines of UN REDD and also validating bodies such as the VCS. The projected returns on some of these projects can be staggering, but whether the market and demand holds up is yet to be seen. Governments in developing countries are often keen to get these investors on-board; it helps to reduce the country’s overall emissions and shows that they are actively keen on development.

Of course the proper capital is also needed to pay for all outgoings; this is often funded by investors into the carbon company’s core fund. There is a risk that if the market demand for carbon credits slides, the interest in these REDD projects may suffer also, with less investment happening and the chance of abandoned projects resulting in increased degradation and greenhouse gas emissions. But the likelihood of this happening is relatively low, as many companies and firms believe that climate change will affect them negatively in some way, and whether through buying CSR credits or investing in a project, they will want to get their share of the market.

Overall, REDD projects could be a good way for coastal conservation managers to guarantee the safety of their environments in a time where funding for regular conservation projects is hard to come by and support from governments in governance and enforcement may be minimal. Examples of successful projects include the Kasigau Corridor Project (Phases I and II) which has created thousands of credits for sale (visit the VCS project database for more information). REDD projects are labour intensive and risky (financially and socioeconomically) but if carried out with rigour and with an interdisciplinary team focused on good governance, conservation and social development then there are few reasons why they should not work.

Melissa Schiele (melissa.schiele@ is Heritage Project Manager and a member of the Marine Biological Association.


Kauffman J.B., Heider C., Cole T.G., Dwire K.A. Donato D.C. (2011) Ecosystem carbon stock of micronesian mangrove forests. Wetlands 31, 343–352.

Pendleton L., Donato D.C., Murray B.C., Crooks S., Jenkins A.W., Sifleet S., Craft C., Fourguean J.W., Kauffmann J.B., Marbà N., Megonigal P., Pidgeon E., Herr D., Gordon D. and Baldera A. (2012) Estimating global ‘blue carbon’ emissions from conversion and degradation of vegetated coastal ecosystems. PLOS 7, e43542. DOI:10.1371/journal.pone.0043542. VCS UN REDD CCBA REDD Monitor (unbiased whistle blower on REDD) Mongabay


Melissa Schiele